Incredible videos: mussel hunting under ice during low tide, others
http://www.youtube.com/watch_popup?v=Z0qGvC3vqaA
Amazing pendulum waves of Mach:
http://sciencedemonstrations.fas.harvard.edu/icb/icb.do?keyword=k16940&pageid=icb.page80863&pageContentId=icb.pagecontent341734&state=maximize&view=view.do&viewParam_name=indepth.html#a_icb_pagecontent341734
Showing posts with label marine bio. Show all posts
Showing posts with label marine bio. Show all posts
Saturday, October 15, 2011
Wednesday, June 8, 2011
Vertebrates "are" Invertebrates
I asked the following questions to Christopher at his blog Catalogue of Organisms, in his post on moths.
PPS. Insect wings appear to be homologs to a vertebrate rib "shell", that is, the delicate forewings of a butterfly are equivalent evolutionarily to the hyperdense ribcage of a dugong, the aftwings of a moth to a sauropod pelvis, the fly's vestigial flight knobs to a giant blue whales vestigial pelvis.
- Are the pharyngeal arches in vertebrates homologous to the first pair of true legs in insects?
- Are the abdomenal prolegs in holometabolous caterpillars homologous to the ventral mammae & milk line in mammals? (both involve fluid-dynamic flow rather than muscle movement, and woulld explain presence of most male mammals retaining vestigial nipples).
I suspect so, in both cases. Having just read The Secret Life of Lobsters by Trevor Corson, I see that female lobsters secrete protein glue (for egg attachment) from cement ducts on their caudalmost swimmerettes (homologous to caudalmost prolegs & mammae secreting casein glue-rich milk IMO). They fold their tails like crabs and deposit thousands of eggs within the folded area, protecting them from exposure. Marsupials seem to have retained this trait, except the marsupial embryo escapes the egg and womb and crawls by forelimbs to the mammae which are protected from exposure by a skin fold (pouch). The echidna, an egg laying primitive monotreme mammal with a pouch, has no external nipples, the hatched infant licks the abdomen to get milk. It appears to be a homology between these distinct taxa.
Aaron Filler's book on Vertebrae called The Upright Ape goes into detail on the spine & vertebrae as archetype, but does not mention this: Lobsters inside their eggs molt 35 times, changing their 'skin'. (After leaving the egg, lobsters eat their shed 'skin'.) The 35 molts produce the somites which form the vertebral column (in vertebrates), internally similar to the external rattles of the molting rattlesnake, I'd say. (Unlike lobsters, snakes never eat their shed skin AFAIK.) It is my contention that the 35 molts are, geometrically, 7 episodes of pentameric (5-way split) distribution, resulting in, for example, 7 cervical vertebrae in mammals, etc.
DDeden
PS. Insect wings and bird/dinosaur feathers appear to be homologous to lobster swimmerettes, (and more distantly to caterpillar prolegs and mammalian mammae). Imagine that! Nature Rules!PPS. Insect wings appear to be homologs to a vertebrate rib "shell", that is, the delicate forewings of a butterfly are equivalent evolutionarily to the hyperdense ribcage of a dugong, the aftwings of a moth to a sauropod pelvis, the fly's vestigial flight knobs to a giant blue whales vestigial pelvis.
http://coo.fieldofscience.com/2011/06/colour-vs-crypsis.html#comments
http://www.amazon.com/Secret-Life-Lobsters-Scientists-Unraveling/dp/0060555580
Also interesting to compare human embryos and giant sauropod dinosaurs:
and the tentacles of squid ((4 + 1) x 2) with the typical prolegs of a caterpillar ((4 + 1) x 2)...
=================================================================
Church forests of Lake Tana, Ethiopia 'Trees are the jewels of God"
http://blogs.plos.org/blog/2011/02/25/church-forest/
They function similarly to the European tradition of Royal Forest. Interesting the name of the island forests is Coptic Forest, similar to Coppice Forest.
Friday, April 30, 2010
Sloths & jitterbugging heart & earth & dive foraging
marine sloth
outhouse sloth
-
layers of the heart
rotary venticular blood flow & torsion of heart muscle similar to VE jitterbug transform, with opposing heart muscle groups (123 45 678) :
article
Note pic 14, similar to tao/dau symbol or rolling surf wave, and general similar form of heart to a marine snail, which filter feeds and breathes by pumping seawater through gills and gut tissue.
"Pettigrew14 performed careful dissection of the heart of mammals and man, demonstrating 7 muscle layers. The three outer layers spiral with an increasing angle from the perpendicular, while the fourth layer is horizontal. The three inner layers spiral in the opposite direction, increasing toward the vertical. The layers are arranged in opposition so that 1 opposes 7, 2 opposes 6, and 3 opposes 5, with the fourth layer being a connecting layer (tensional frame?)."
jitterbug
-
6,000 year old human artifacts contains indications of 3/4 protein from marine diet
Quantitative evaluation of marine protein contribution in ancient diets
based on nitrogen isotope ratios of individual amino acids in bone collagen:
An investigation at the Kitakogane Jomon site
YI Naito, NV Honch, Y Chikaraishi, N Ohkouchi, M Yoneda 2010 AJPA
Nitrogen stable isotopes analysis of individual bone collagen amino acids
was applied to archeological samples as a new tool for assessing the
composition of ancient human diets and calibrating radiocarbon dates. We
used this technique to investigate human and faunal samples from the
Kitakogane shell midden in Hokkaido, Japan (5,300-6,000 cal BP). Using
compound-specific nitrogen isotope analysis of individual amino acids, we
aimed to estimate i) the quantitative contribution of marine and terrestrial
protein to the human diet, and ii) the mean trophic level (TL) from which
dietary protein was derived from marine ecosystems. Data were interpreted
with reference to the amino acid trophic level (TLAA) model, which uses
empirical amino acid 15N from modern marine fauna to construct mathematical
equations that predict the trophic position of organisms. The TLAA model
produced realistic TL estimates for the Kitakogane marine animals. However,
this model was not appropriate for the interpretation of human amino acid
15N, as dietary protein is derived from both marine and terrestrial
environments. Hence, we developed a series of relevant equations that
considered the consumption of dietary resources from both ecosystems. Using
these equations, the mean percentage of marine protein in the Kitakogane
human diet was estimated to be 74%.
-
Diaphragmatic contractions pump oxygen to the brain during hypoxia, increasing the cerebral blood flow volume. Involuntary breathing movements improve cerebral o... [J Appl Physiol. 2009] - PubMed result
We investigated whether the involuntary breathing movements (IBM) during the struggle phase of breath holding, together with peripheral vasoconstriction and progressive hypercapnia, have a positive effect in maintaining cerebral blood volume. The central hemodynamics, arterial oxygen saturation, brain regional oxyhemoglobin (bHbO(2)), deoxyhemoglobin, and total hemoglobin changes and IBM were monitored during maximal dry breath holds in eight elite divers. The frequency of IBM increased (by approximately 100%), and their duration decreased ( approximately 30%), toward the end of the struggle phase, whereas the amplitude was unchanged (compared with the beginning of the struggle phase). In all subjects, a consistent increase in brain regional deoxyhemoglobin and total hemoglobin was also found during struggle phase, whereas bHbO(2) changed biphasically: it initially increased until the middle of the struggle phase, with the subsequent relative decline at the end of the breath hold. Mean arterial pressure was elevated during the struggle phase, although there was no further rise in the peripheral resistance, suggesting unchanged peripheral vasoconstriction and implying the beneficial influence of the IBM on the cardiac output recovery (primarily by restoration of the stroke volume). The IBM-induced short-lasting, sudden increases in mean arterial pressure were followed by similar oscillations in bHbO(2). These results suggest that an increase in the cerebral blood volume observed during the struggle phase of dry apnea is most likely caused by the IBM at the time of the hypercapnia-induced cerebral vasodilatation and peripheral vasoconstriction.
-
Levant 800ka - (Hula/Jordan, fire, food prep) African Rift drought
doi 10.1016/j.jhevol.2010.03.007
The paleoclimate of the Eastern Mediterranean during the transition from
early to mid Pleistocene (900 to 700 ka) based on marine and non-marine
records: an integrated overview
Ahuva Almogi-Labin 2010 JHE
Climate change is frequently considered an important driver of hominin
evolution and dispersal patterns. The role of climate change in the last
phase (900700 ka) of the Middle Pleistocene Transition (MPT) in the Levant
and northeast Africa was examined, using marine and non-marine records.
During the MPT the global climate system shifted from a linear 41 k.yr. into
a highly non-linear 100 k.yr. system, considerably changing its global
modulation. Northeast Africa aridity further intensified around 950 ka, as
indicated by a sharp increase in dust flux, and a jump to overall higher
levels thereafter, coinciding with a lack of sapropels in the deep eastern
Mediterranean (930690 ka). The increased dust flux centering at 800 ka
corresponds to the minima in 400 k.yr. eccentricity, a minima in 65 °N solar
forcing and in the weakest African monsoon precession periodicity. This
resulted in expansion of hyper-arid conditions across North Africa, the
lowest lake levels in eastern Africa and the lowest rainfall in the Nile
River headwaters. In the eastern Mediterranean an increasing continental
signature is seen in glacial stages 22 (880 ka) and 20 (800 ka). Lower
arboreal pollen values also indicate arid conditions during these glacial
stages. The southern and eastern parts of the Negev Desert, unlike its
northern part, were hyper-arid during the MPT, making them highly
unsustainable. The fluctuations in the stands of Lake Amora follow global
climate variability but were more moderate than those of its last glacial
Lake Lisan successor. In the northern Jordan-Valley Hula Lake, frequent
fluctuations in lake level coincide with both global climate changes and
minor changes in water salinity varying from fresh to oligohaline. It
appears therefore that the most pronounced and widespread deterioration in
climate occurred in northeast Africa from 900 to 700 ka, whereas in the
Levant the corresponding climatic changes were more moderate.
-
Warmbloodedness & respiration in dinosaurs and mammoths
A Clarke & H-O Poertner 2010 Biol.Rev.PRESS
Temperature, metabolic power, and the evolution of endothermy
Endothermy has evolved at least twice, in the precursors to modern mammals
and birds. The most widely accepted explanation for the evolution of
endothermy has been selection for enhanced aerobic capacity. We review this
hypothesis in the light of advances in our understanding of ATP generation
by mitochondria and muscle performance. Together with the development of
isotope-based techniques for the measurement of metabolic rate in
free-ranging vertebrates, these have confirmed the importance of aerobic
scope in the evolution of endothermy: absolute aerobic scope, ATP generation
by mitochondria, and muscle power output are all strongly
temperature-dependent, indicating that there would have been significant
improvement in whole-organism locomotor ability with a warmer body. New data
on mitochondrial ATP generation and proton leak suggest that the thermal
physiology of mitochondria may differ between organisms of contrasting
ecology and thermal flexibility. Together with recent biophysical modelling,
this strengthens the long-held view that endothermy originated in smaller,
active eurythermal ectotherms living in a cool but variable thermal
environment. We propose that rather than being a secondary consequence of
the evolution of an enhanced aerobic scope, a warmer body was the means by
which that enhanced aerobic scope was achieved. This modified hypothesis
requires that the rise in metabolic rate, and the insulation necessary to
retain metabolic heat, arose early in the lineages leading to birds and
mammals. Large dinosaurs were warm, but were not endotherms, and the
metabolic status of pterosaurs remains unresolved.
KL Campbell cs 2010 Nature Genetics PRESS
Substitutions in woolly mammoth hemoglobin confer biochemical properties
adaptive for cold tolerance
We have genetically retrieved, resurrected and performed detailed
structure-function analyses on authentic woolly mammoth hemoglobin to reveal
for the first time both the evolutionary origins and the structural
underpinnings of a key adaptive physiochemical trait in an extinct species.
Hemoglobin binds and carries O2; however, its ability to offload O2 to
respiring cells is hampered at low temperatures, as heme deoxygenation is
inherently endothermic (that is, hemoglobin-O2 affinity increases as
temperature decreases). We identify amino acid substitutions with large
phenotypic effect on the chimeric ¦Â/¦Ä-globin subunit of mammoth
hemoglobin
that provide a unique solution to this problem and thereby minimize
energetically costly heat loss. This biochemical specialization may have
been involved in the exploitation of high-latitude environments by this
African-derived elephantid lineage during the Pleistocene period. This
powerful new approach to directly analyze the genetic and structural basis
of physiological adaptations in an extinct species adds an important new
dimension to the study of natural selection.
outhouse sloth
-
layers of the heart
rotary venticular blood flow & torsion of heart muscle similar to VE jitterbug transform, with opposing heart muscle groups (123 45 678) :
article
Note pic 14, similar to tao/dau symbol or rolling surf wave, and general similar form of heart to a marine snail, which filter feeds and breathes by pumping seawater through gills and gut tissue.
"Pettigrew14 performed careful dissection of the heart of mammals and man, demonstrating 7 muscle layers. The three outer layers spiral with an increasing angle from the perpendicular, while the fourth layer is horizontal. The three inner layers spiral in the opposite direction, increasing toward the vertical. The layers are arranged in opposition so that 1 opposes 7, 2 opposes 6, and 3 opposes 5, with the fourth layer being a connecting layer (tensional frame?)."
jitterbug
-
6,000 year old human artifacts contains indications of 3/4 protein from marine diet
Quantitative evaluation of marine protein contribution in ancient diets
based on nitrogen isotope ratios of individual amino acids in bone collagen:
An investigation at the Kitakogane Jomon site
YI Naito, NV Honch, Y Chikaraishi, N Ohkouchi, M Yoneda 2010 AJPA
Nitrogen stable isotopes analysis of individual bone collagen amino acids
was applied to archeological samples as a new tool for assessing the
composition of ancient human diets and calibrating radiocarbon dates. We
used this technique to investigate human and faunal samples from the
Kitakogane shell midden in Hokkaido, Japan (5,300-6,000 cal BP). Using
compound-specific nitrogen isotope analysis of individual amino acids, we
aimed to estimate i) the quantitative contribution of marine and terrestrial
protein to the human diet, and ii) the mean trophic level (TL) from which
dietary protein was derived from marine ecosystems. Data were interpreted
with reference to the amino acid trophic level (TLAA) model, which uses
empirical amino acid 15N from modern marine fauna to construct mathematical
equations that predict the trophic position of organisms. The TLAA model
produced realistic TL estimates for the Kitakogane marine animals. However,
this model was not appropriate for the interpretation of human amino acid
15N, as dietary protein is derived from both marine and terrestrial
environments. Hence, we developed a series of relevant equations that
considered the consumption of dietary resources from both ecosystems. Using
these equations, the mean percentage of marine protein in the Kitakogane
human diet was estimated to be 74%.
-
Diaphragmatic contractions pump oxygen to the brain during hypoxia, increasing the cerebral blood flow volume. Involuntary breathing movements improve cerebral o... [J Appl Physiol. 2009] - PubMed result
We investigated whether the involuntary breathing movements (IBM) during the struggle phase of breath holding, together with peripheral vasoconstriction and progressive hypercapnia, have a positive effect in maintaining cerebral blood volume. The central hemodynamics, arterial oxygen saturation, brain regional oxyhemoglobin (bHbO(2)), deoxyhemoglobin, and total hemoglobin changes and IBM were monitored during maximal dry breath holds in eight elite divers. The frequency of IBM increased (by approximately 100%), and their duration decreased ( approximately 30%), toward the end of the struggle phase, whereas the amplitude was unchanged (compared with the beginning of the struggle phase). In all subjects, a consistent increase in brain regional deoxyhemoglobin and total hemoglobin was also found during struggle phase, whereas bHbO(2) changed biphasically: it initially increased until the middle of the struggle phase, with the subsequent relative decline at the end of the breath hold. Mean arterial pressure was elevated during the struggle phase, although there was no further rise in the peripheral resistance, suggesting unchanged peripheral vasoconstriction and implying the beneficial influence of the IBM on the cardiac output recovery (primarily by restoration of the stroke volume). The IBM-induced short-lasting, sudden increases in mean arterial pressure were followed by similar oscillations in bHbO(2). These results suggest that an increase in the cerebral blood volume observed during the struggle phase of dry apnea is most likely caused by the IBM at the time of the hypercapnia-induced cerebral vasodilatation and peripheral vasoconstriction.
-
Levant 800ka - (Hula/Jordan, fire, food prep) African Rift drought
doi 10.1016/j.jhevol.2010.03.007
The paleoclimate of the Eastern Mediterranean during the transition from
early to mid Pleistocene (900 to 700 ka) based on marine and non-marine
records: an integrated overview
Ahuva Almogi-Labin 2010 JHE
Climate change is frequently considered an important driver of hominin
evolution and dispersal patterns. The role of climate change in the last
phase (900700 ka) of the Middle Pleistocene Transition (MPT) in the Levant
and northeast Africa was examined, using marine and non-marine records.
During the MPT the global climate system shifted from a linear 41 k.yr. into
a highly non-linear 100 k.yr. system, considerably changing its global
modulation. Northeast Africa aridity further intensified around 950 ka, as
indicated by a sharp increase in dust flux, and a jump to overall higher
levels thereafter, coinciding with a lack of sapropels in the deep eastern
Mediterranean (930690 ka). The increased dust flux centering at 800 ka
corresponds to the minima in 400 k.yr. eccentricity, a minima in 65 °N solar
forcing and in the weakest African monsoon precession periodicity. This
resulted in expansion of hyper-arid conditions across North Africa, the
lowest lake levels in eastern Africa and the lowest rainfall in the Nile
River headwaters. In the eastern Mediterranean an increasing continental
signature is seen in glacial stages 22 (880 ka) and 20 (800 ka). Lower
arboreal pollen values also indicate arid conditions during these glacial
stages. The southern and eastern parts of the Negev Desert, unlike its
northern part, were hyper-arid during the MPT, making them highly
unsustainable. The fluctuations in the stands of Lake Amora follow global
climate variability but were more moderate than those of its last glacial
Lake Lisan successor. In the northern Jordan-Valley Hula Lake, frequent
fluctuations in lake level coincide with both global climate changes and
minor changes in water salinity varying from fresh to oligohaline. It
appears therefore that the most pronounced and widespread deterioration in
climate occurred in northeast Africa from 900 to 700 ka, whereas in the
Levant the corresponding climatic changes were more moderate.
-
Warmbloodedness & respiration in dinosaurs and mammoths
A Clarke & H-O Poertner 2010 Biol.Rev.PRESS
Temperature, metabolic power, and the evolution of endothermy
Endothermy has evolved at least twice, in the precursors to modern mammals
and birds. The most widely accepted explanation for the evolution of
endothermy has been selection for enhanced aerobic capacity. We review this
hypothesis in the light of advances in our understanding of ATP generation
by mitochondria and muscle performance. Together with the development of
isotope-based techniques for the measurement of metabolic rate in
free-ranging vertebrates, these have confirmed the importance of aerobic
scope in the evolution of endothermy: absolute aerobic scope, ATP generation
by mitochondria, and muscle power output are all strongly
temperature-dependent, indicating that there would have been significant
improvement in whole-organism locomotor ability with a warmer body. New data
on mitochondrial ATP generation and proton leak suggest that the thermal
physiology of mitochondria may differ between organisms of contrasting
ecology and thermal flexibility. Together with recent biophysical modelling,
this strengthens the long-held view that endothermy originated in smaller,
active eurythermal ectotherms living in a cool but variable thermal
environment. We propose that rather than being a secondary consequence of
the evolution of an enhanced aerobic scope, a warmer body was the means by
which that enhanced aerobic scope was achieved. This modified hypothesis
requires that the rise in metabolic rate, and the insulation necessary to
retain metabolic heat, arose early in the lineages leading to birds and
mammals. Large dinosaurs were warm, but were not endotherms, and the
metabolic status of pterosaurs remains unresolved.
KL Campbell cs 2010 Nature Genetics PRESS
Substitutions in woolly mammoth hemoglobin confer biochemical properties
adaptive for cold tolerance
We have genetically retrieved, resurrected and performed detailed
structure-function analyses on authentic woolly mammoth hemoglobin to reveal
for the first time both the evolutionary origins and the structural
underpinnings of a key adaptive physiochemical trait in an extinct species.
Hemoglobin binds and carries O2; however, its ability to offload O2 to
respiring cells is hampered at low temperatures, as heme deoxygenation is
inherently endothermic (that is, hemoglobin-O2 affinity increases as
temperature decreases). We identify amino acid substitutions with large
phenotypic effect on the chimeric ¦Â/¦Ä-globin subunit of mammoth
hemoglobin
that provide a unique solution to this problem and thereby minimize
energetically costly heat loss. This biochemical specialization may have
been involved in the exploitation of high-latitude environments by this
African-derived elephantid lineage during the Pleistocene period. This
powerful new approach to directly analyze the genetic and structural basis
of physiological adaptations in an extinct species adds an important new
dimension to the study of natural selection.
Monday, February 22, 2010
Air Air everywhere
Diving physiology bio-chem: respiration, apnea
Divers should not hyperventilate causing alkalosis in blood, due to susceptibility to sudden black-out from lack of oxygen (with no chemoreceptor warning).
Rather they should be neutral pH, during dive the accumulation of carbon dioxide produces acidosis in the blood (even if there is abundant oxygen) which in MDR (mammalian divers reflex) is a safer mode, high CO2 triggers air hunger (oxygen conservation) and diaphragmatic contractions pump O2 & CO2 around efficiently.
REFINING THE BREATH by DOUG KELLER 2007
And then there are times when we anticipate physical stress and begin to breathe harder, using the chest muscles. The problem is that this situation of persistent mental and emotional stress has become more the rule of daily life than the exception. The body is on constant alert via the sympathetic nervous system, but the physical exertion — and the need for accelerated breathing — never comes. As a result, we’ve both pumped in more oxygen and pumped out carbon dioxide in this process of hyperventilation, and a vital chemical balance in the body has been seriously upset.
Here begins the vicious cycle that is so familiar to hyperventilators. The harder we breathe, the more oxygen-starved we feel, and we can’t ‘catch’ our breath. This is not for lack of oxygen, but because so much carbon dioxide has been forced out in the process of overbreathing. The presence of carbon dioxide in our blood allows the hemoglobins to transport oxygen to the body’s tissues. If too much carbon dioxide is ‘blown off’ by hyperventilation, the blood becomes alkaline, and the hemoglobin can’t release the oxygen molecules, which are chemically ‘stuck’ to it. The blood is carrying around plenty of oxygen: the problem is that the body can’t get any of it!
Carbon dioxide also provides the chemical message in the blood that leads us to take our next breath. At the end of the exhalation, there is a natural, restful pause before we breathe in again. During that pause, carbon dioxide builds up in the blood at the same time that oxygen is being released into the tissues. When it reaches a certain level, the respiratory center of the brain sends a signal through the phrenic nerve to the diaphragm to take another breath.
In the normal course of breathing, the entire process of respiration is driven by carbon dioxide, from the first neurochemical impulse that initiates the inhalation, to the chemical balancing act in the blood that delivers oxygen to the body. All of this happens without our having to think about or consciously direct the process, and the whole process works astoundingly well, with carbon dioxide playing a central role from beginning to end.
That, of course, describes the natural process of the breath, in which the conscious mind, with its slurry of desire, emotion and expectation, is not factored in. But what happens when we overbreathe? Usually an excess of carbon dioxide in the blood tells us to take another breath in, and the process is quite relaxed. But when carbon dioxide drops below a certain level (due to anticipatory fast hard breathing), the message from the body — which is now not receiving the oxygen it needs — is that we are suffocating! And so the breath is driven by the body’s panic, and we breathe harder, making the situation worse instead of better. A subtle chemical imbalance soon becomes a full-blown panic attack. The age-old cure for panic attacks — to breathe into a paper bag — has a very good biochemical basis: it’s meant to increase the levels of carbon dioxide by re-breathing the same air, until the proper balance is restored.
When it comes to stressful breathing patterns, or patterns of ‘overbreathing, certainly the vicious cycle of the biochemistry of hyperventilation plays the part of gasoline thrown on the fire. Mental anticipation and anxiety, however, is the match that lights the fire.
-
So relax, and just glow a little. ;)
h/t kelp princess @ Deeper Blue
Divers should not hyperventilate causing alkalosis in blood, due to susceptibility to sudden black-out from lack of oxygen (with no chemoreceptor warning).
Rather they should be neutral pH, during dive the accumulation of carbon dioxide produces acidosis in the blood (even if there is abundant oxygen) which in MDR (mammalian divers reflex) is a safer mode, high CO2 triggers air hunger (oxygen conservation) and diaphragmatic contractions pump O2 & CO2 around efficiently.
REFINING THE BREATH by DOUG KELLER 2007
And then there are times when we anticipate physical stress and begin to breathe harder, using the chest muscles. The problem is that this situation of persistent mental and emotional stress has become more the rule of daily life than the exception. The body is on constant alert via the sympathetic nervous system, but the physical exertion — and the need for accelerated breathing — never comes. As a result, we’ve both pumped in more oxygen and pumped out carbon dioxide in this process of hyperventilation, and a vital chemical balance in the body has been seriously upset.
Here begins the vicious cycle that is so familiar to hyperventilators. The harder we breathe, the more oxygen-starved we feel, and we can’t ‘catch’ our breath. This is not for lack of oxygen, but because so much carbon dioxide has been forced out in the process of overbreathing. The presence of carbon dioxide in our blood allows the hemoglobins to transport oxygen to the body’s tissues. If too much carbon dioxide is ‘blown off’ by hyperventilation, the blood becomes alkaline, and the hemoglobin can’t release the oxygen molecules, which are chemically ‘stuck’ to it. The blood is carrying around plenty of oxygen: the problem is that the body can’t get any of it!
Carbon dioxide also provides the chemical message in the blood that leads us to take our next breath. At the end of the exhalation, there is a natural, restful pause before we breathe in again. During that pause, carbon dioxide builds up in the blood at the same time that oxygen is being released into the tissues. When it reaches a certain level, the respiratory center of the brain sends a signal through the phrenic nerve to the diaphragm to take another breath.
In the normal course of breathing, the entire process of respiration is driven by carbon dioxide, from the first neurochemical impulse that initiates the inhalation, to the chemical balancing act in the blood that delivers oxygen to the body. All of this happens without our having to think about or consciously direct the process, and the whole process works astoundingly well, with carbon dioxide playing a central role from beginning to end.
That, of course, describes the natural process of the breath, in which the conscious mind, with its slurry of desire, emotion and expectation, is not factored in. But what happens when we overbreathe? Usually an excess of carbon dioxide in the blood tells us to take another breath in, and the process is quite relaxed. But when carbon dioxide drops below a certain level (due to anticipatory fast hard breathing), the message from the body — which is now not receiving the oxygen it needs — is that we are suffocating! And so the breath is driven by the body’s panic, and we breathe harder, making the situation worse instead of better. A subtle chemical imbalance soon becomes a full-blown panic attack. The age-old cure for panic attacks — to breathe into a paper bag — has a very good biochemical basis: it’s meant to increase the levels of carbon dioxide by re-breathing the same air, until the proper balance is restored.
When it comes to stressful breathing patterns, or patterns of ‘overbreathing, certainly the vicious cycle of the biochemistry of hyperventilation plays the part of gasoline thrown on the fire. Mental anticipation and anxiety, however, is the match that lights the fire.
-
So relax, and just glow a little. ;)
h/t kelp princess @ Deeper Blue
Sunday, January 3, 2010
Shellfish saved humans but not AAT!!??
Humans: Mammals of the Seashores
Video
Shellfish fed human ancestors
map & photo of Buia & Djibouti bays
(Note similarity and nearness to Djibouti harbor just south along coast, with islands offshore rich in coral reefs and mangroves. During a slightly wetter period, paradise, but now desert isles.)
1ma beef at Buia, Eritrea: Surf & Turf at tropical lagoons
Surf & Turf @ coast
Dahlak archipelago settled 2ka, speak Dahalik dialect of Tigrinya, pastoral/fishing/pearl diving
-
Epic of Gilgamesh/Noah's ark was round
http://www.guardian.co.uk/uk/2010/jan/01/noahs-ark-was-circular
similar to the marsh Arab barns or coracles?
Finkel's research throws light on the familiar Mesopotamian story, which became the account in Genesis, in the Old Testament, of Noah and the ark that saved his menagerie from the waters which drowned every other living thing on earth.
In his translation, the god who has decided to spare one just man speaks to Atram-Hasis, a Sumerian king who lived before the flood and who is the Noah figure in earlier versions of the ark story. "Wall, wall! Reed wall, reed wall! Atram-Hasis, pay heed to my advice, that you may live forever! Destroy your house, build a boat; despise possessions And save life! Draw out the boat that you will built with a circular design; Let its length and breadth be the same."
The tablet goes on to command the use of plaited palm fibre, waterproofed with bitumen, before the construction of cabins for the people and wild animals.
-
50,000 year old pigments in shells for body paint
paint or mosquito repellant?
Scientists unearthed the shells at two archaeological sites in the Murcia province of southern Spain. Professor Joao Zilhao, the archaeologist from Bristol University in the UK, who led the study, said that he and his team had examined shells that were used as containers to mix and store pigments. Black sticks of the pigment manganese, which may have been used as body paint by Neanderthals, have previously been discovered in Africa. "[But] this is the first secure evidence for their use of cosmetics," he told BBC News. "The use of these complex recipes is new. It's more than body painting." The scientists found lumps of a yellow pigment, that they say was possibly used as a foundation. They also found red powder mixed up with flecks of a reflective brilliant black mineral. The shells were coated with residues of mixed pigments
Some of the sculpted, brightly coloured shells may also have been worn by Neanderthals as jewellery. [I think this was H sapiens, not neandertals.]
-
My dear sir, in this world it is not so easy to settle these plain things. I have ever found your plain things the knottiest of all.
- Moby-Dick by Herman Melville
________
'We are coming now rather into the region of guesswork', said Dr Mortimer.
'Say, rather, into the region where we balance probabilities and choose the most likely. It is the scientific use of the imagination, but we have always some material basis on which to start our speculation', [replied Holmes].
- The Hound of the Baskervilles by Arthur Conan Doyle
-----------
"The whole aim of practical politics is to keep the populace alarmed -- and
thus clamorous to be led to safety -- by menacing it with an endless series
of hobglobins, all of them imaginary." -- H.L. Mencken
-
Some years ago — it was February, 1955, late in the southern summer — I was introduced by Professor Raymond A. Dart to a room filled with fossil bones in the basement of Johannesburg's Medical School. In that room I met more than bones, for I encountered a variety of things that I had never heard of. I had never heard of man's origin on the continent of Africa. I had never heard of our probable ancestors, the australopithecines, a zoological group of small-brained erect-running creatures, hesitating between the roles of ape and man, who haunted the high African savannahs a million or two years ago.
Authors, being shameless, tend to rush into print. So fathomless was my ignorance, however, and so oceanic were the dimensions of scientific accomplishment while my back had been turned, that the rush consumed six years of my life, and even then I learned only to float. For it was not just a matter of Australopithecus and the predatory transition; there were alpha fish and pecking orders, gene pools and displacement activities, exploratory behavior and ritualized aggression, and all had bearing on the human condition. Above all, there was territory.
Robert Ardrey - The Territoreal Imperative
-
Babble from Bab-El, syllabic phonetic language roots in Hebrew/Arabic/Phoenician/Venetian
http://www.edenics.org/
-
SS Earth http://en.wikipedia.org/wiki/Operating_Manual_for_Spaceship_Earth
Spaceship earth: The idea that the earth is a spaceship, with the sun as our energy supplier.
General systems theory: The idea of the earth is as a mechanical vehicle that requires maintenance, and that if you do not keep it in good order it will cease to function.
Synergy: Likens humanity to a chick that has just broken out of its shell and is now ready to enter the next phase of its existence. Suggests "How big can we think?"
Integral functions: Where the whole of a system is greater than the sum of its parts. "Ergo, only complete world desovereignization can permit the realization of an all humanity high standard support."
Regenerative landscape: Wealth is expanded by the development of tools which go beyond what was integral to man. States that the highest priority need of world society is a realistic accounting system, instead of one where a top toolmaker in India gets paid in a month what he would make in a day in Detroit. Defines tools as either craft tools that can be invented by one man such as bows and arrows and industrial tools that can not be produced by one man such as the S.S. Queen Mary. Finds language to be the first industrial tool. States that craft tools were used to create industrial tools. States that to take advantage of potential wealth we must give life fellowships to each person who is or becomes unemployed, and states that for every 100,000 fellowships given out one person will come up with something so valuable that it will pay for the remaining 99,999 fellowships. Predicts that soon the great office buildings will be turned into residences and that all the work that had been done in them will be done in the basements of a few buildings. States that we "must operate exclusively on our vast daily energy income from the powers of wind, tide, water, and the direct Sun radiation energy".
This quotation, referring to fossil fuels, reflects his approach:
"...can make all of humanity successful through science's world-engulfing industrial evolution provided that we are not so foolish as to continue to exhaust in a split second of astronomical history the orderly energy savings of billions of years' energy conservation aboard our Spaceship Earth. These energy savings have been put into our Spaceship's life-regeneration-guaranteeing bank account for use only in self-starter functions."
"Spaceship earth" may have been derived from a passage in Henry George's best known work, Progress and Poverty[1] (1879). From book IV, chapter 2:
It is a well-provisioned ship, this on which we sail through space. If the bread and beef above decks seem to grow scarce, we but open a hatch and there is a new supply, of which before we never dreamed. And very great command over the services of others comes to those who as the hatches are opened are permitted to say, "This is mine!"
-
Darwin's Origin of Species, David Winters @ Atavism blog:
http://sciblogs.co.nz/the-atavism/2009/12/31/the-origin-of-species-and-the-origin-of-species/
Biological speciation vs Social specialization.
species: separate full-time from parent group type due to divergent geo/bio-niche
specialists: separate part-time from parent group type
"You can see where my number came from once you consider that only about 4% of the genome is functional DNA - 150 mutations in your genome will lead to about 6 mutations in functional regions."
Video
Shellfish fed human ancestors
map & photo of Buia & Djibouti bays
(Note similarity and nearness to Djibouti harbor just south along coast, with islands offshore rich in coral reefs and mangroves. During a slightly wetter period, paradise, but now desert isles.)
1ma beef at Buia, Eritrea: Surf & Turf at tropical lagoons
Surf & Turf @ coast
Dahlak archipelago settled 2ka, speak Dahalik dialect of Tigrinya, pastoral/fishing/pearl diving
-
Epic of Gilgamesh/Noah's ark was round
http://www.guardian.co.uk/uk/2010/jan/01/noahs-ark-was-circular
similar to the marsh Arab barns or coracles?
Finkel's research throws light on the familiar Mesopotamian story, which became the account in Genesis, in the Old Testament, of Noah and the ark that saved his menagerie from the waters which drowned every other living thing on earth.
In his translation, the god who has decided to spare one just man speaks to Atram-Hasis, a Sumerian king who lived before the flood and who is the Noah figure in earlier versions of the ark story. "Wall, wall! Reed wall, reed wall! Atram-Hasis, pay heed to my advice, that you may live forever! Destroy your house, build a boat; despise possessions And save life! Draw out the boat that you will built with a circular design; Let its length and breadth be the same."
The tablet goes on to command the use of plaited palm fibre, waterproofed with bitumen, before the construction of cabins for the people and wild animals.
-
50,000 year old pigments in shells for body paint
paint or mosquito repellant?
Scientists unearthed the shells at two archaeological sites in the Murcia province of southern Spain. Professor Joao Zilhao, the archaeologist from Bristol University in the UK, who led the study, said that he and his team had examined shells that were used as containers to mix and store pigments. Black sticks of the pigment manganese, which may have been used as body paint by Neanderthals, have previously been discovered in Africa. "[But] this is the first secure evidence for their use of cosmetics," he told BBC News. "The use of these complex recipes is new. It's more than body painting." The scientists found lumps of a yellow pigment, that they say was possibly used as a foundation. They also found red powder mixed up with flecks of a reflective brilliant black mineral. The shells were coated with residues of mixed pigments
Some of the sculpted, brightly coloured shells may also have been worn by Neanderthals as jewellery. [I think this was H sapiens, not neandertals.]
-
My dear sir, in this world it is not so easy to settle these plain things. I have ever found your plain things the knottiest of all.
- Moby-Dick by Herman Melville
________
'We are coming now rather into the region of guesswork', said Dr Mortimer.
'Say, rather, into the region where we balance probabilities and choose the most likely. It is the scientific use of the imagination, but we have always some material basis on which to start our speculation', [replied Holmes].
- The Hound of the Baskervilles by Arthur Conan Doyle
-----------
"The whole aim of practical politics is to keep the populace alarmed -- and
thus clamorous to be led to safety -- by menacing it with an endless series
of hobglobins, all of them imaginary." -- H.L. Mencken
-
Some years ago — it was February, 1955, late in the southern summer — I was introduced by Professor Raymond A. Dart to a room filled with fossil bones in the basement of Johannesburg's Medical School. In that room I met more than bones, for I encountered a variety of things that I had never heard of. I had never heard of man's origin on the continent of Africa. I had never heard of our probable ancestors, the australopithecines, a zoological group of small-brained erect-running creatures, hesitating between the roles of ape and man, who haunted the high African savannahs a million or two years ago.
Authors, being shameless, tend to rush into print. So fathomless was my ignorance, however, and so oceanic were the dimensions of scientific accomplishment while my back had been turned, that the rush consumed six years of my life, and even then I learned only to float. For it was not just a matter of Australopithecus and the predatory transition; there were alpha fish and pecking orders, gene pools and displacement activities, exploratory behavior and ritualized aggression, and all had bearing on the human condition. Above all, there was territory.
Robert Ardrey - The Territoreal Imperative
-
Babble from Bab-El, syllabic phonetic language roots in Hebrew/Arabic/Phoenician/Venetian
http://www.edenics.org/
-
SS Earth http://en.wikipedia.org/wiki/Operating_Manual_for_Spaceship_Earth
Spaceship earth: The idea that the earth is a spaceship, with the sun as our energy supplier.
General systems theory: The idea of the earth is as a mechanical vehicle that requires maintenance, and that if you do not keep it in good order it will cease to function.
Synergy: Likens humanity to a chick that has just broken out of its shell and is now ready to enter the next phase of its existence. Suggests "How big can we think?"
Integral functions: Where the whole of a system is greater than the sum of its parts. "Ergo, only complete world desovereignization can permit the realization of an all humanity high standard support."
Regenerative landscape: Wealth is expanded by the development of tools which go beyond what was integral to man. States that the highest priority need of world society is a realistic accounting system, instead of one where a top toolmaker in India gets paid in a month what he would make in a day in Detroit. Defines tools as either craft tools that can be invented by one man such as bows and arrows and industrial tools that can not be produced by one man such as the S.S. Queen Mary. Finds language to be the first industrial tool. States that craft tools were used to create industrial tools. States that to take advantage of potential wealth we must give life fellowships to each person who is or becomes unemployed, and states that for every 100,000 fellowships given out one person will come up with something so valuable that it will pay for the remaining 99,999 fellowships. Predicts that soon the great office buildings will be turned into residences and that all the work that had been done in them will be done in the basements of a few buildings. States that we "must operate exclusively on our vast daily energy income from the powers of wind, tide, water, and the direct Sun radiation energy".
This quotation, referring to fossil fuels, reflects his approach:
"...can make all of humanity successful through science's world-engulfing industrial evolution provided that we are not so foolish as to continue to exhaust in a split second of astronomical history the orderly energy savings of billions of years' energy conservation aboard our Spaceship Earth. These energy savings have been put into our Spaceship's life-regeneration-guaranteeing bank account for use only in self-starter functions."
"Spaceship earth" may have been derived from a passage in Henry George's best known work, Progress and Poverty[1] (1879). From book IV, chapter 2:
It is a well-provisioned ship, this on which we sail through space. If the bread and beef above decks seem to grow scarce, we but open a hatch and there is a new supply, of which before we never dreamed. And very great command over the services of others comes to those who as the hatches are opened are permitted to say, "This is mine!"
-
Darwin's Origin of Species, David Winters @ Atavism blog:
http://sciblogs.co.nz/the-atavism/2009/12/31/the-origin-of-species-and-the-origin-of-species/
Biological speciation vs Social specialization.
species: separate full-time from parent group type due to divergent geo/bio-niche
specialists: separate part-time from parent group type
"You can see where my number came from once you consider that only about 4% of the genome is functional DNA - 150 mutations in your genome will lead to about 6 mutations in functional regions."
Friday, August 21, 2009
Humboldt Natural History Museum closure
http://www.northcoastjournal.com/blogthing/2009/08/07/hsu-natural-history-museum-close/
Local (Humboldt county) North Coast Natural History Museum, associated with Humboldt State University, may be soon closing. They've had a good exhibit on ancient hominids, and always whale fossils and various coastal species.
Being right on the Pacific coast and Redwood forest and linked to HSU marine/envirinmental/forestry studies. A small museum, nothing fancy. This area is economically depressed but ecologically wealthy.
Sociopolitical economic freeze,
Priorities and opportunities,
Sparks blowing in a hot breeze,
Halt the growing of li'l trees.
http://www.humboldt.edu/~natmus/
Introduction
http://savethenorthcoastnhm.org/index.php?q=civicrm/contribute/transact&reset=1&id=3&widgetID=1
If you can and wish to donate some spare funding
[The ARC has no direct affiliation with the museum, but is considering a potential link via ARC-AID-A, a not-for-profit program being considered.]
http://redwoods.info/showrecord.asp?id=243
-
http://www.krisweb.com/krishumboldtbay/krisdb/html/krisweb/whats_new.htm
"So long as our relationship is defined by our differences,
we will empower those who sow hatred rather than peace".
Tuesday, January 6, 2009
Marine monuments & Wing diving
http://news.yahoo.com/s/ap/20090106/ap_on_go_pr_wh/bush_marine_conservation_5
http://www.whitehouse.gov/news/releases/2009/01/20090106-7.html
Establishment of the Rose Atoll Marine National Monument
map
mahalo!
DDeden
kanaka haoli maoli
pakeha maori
papalani fufu
matsaleh bule
If any female (as dive partner) would like to join me in starting Islamarina Dive Clinic, partly based at Rose Atoll, American Samoa, USA, please email me at daud.deden@gmail.com, entitle it "DIVING". Rose Atoll is the southern-most land of the United States and the easternmost isle of the Malayo-Polynesian Samoan islands, and located south of the equator. I am very motivated to begin testing of the ARC there due to the warm clear lagoons and pristine environment. Collaborative non-competitive dive partnership preferred, the focus will be on natural aqua-photic respiratory cycle diving while evidence foraging, theory testing and photo-videographing. An internship may be possible in future, haven't worked out administrative details or funding yet. Come make a dream happen.
wingsuit base jumping from Ali on Vimeo.
Wednesday, November 26, 2008
Orbits, eyeballs and opthamology
trivia: Can you see what I see? I'm trying to see how respiratory cycles, circadian rhythms, accomodation, dark adaptation, pupillary light reflex, photic sneezing and trigeminal nerve and oculomotor nerve work together in humans in air and water, especially with reference to humans apnea diving to dark depths and focusing on food gathering, surfacing and speedy exhalation, and alternatively backfloating while resting in the mid-day sunlight. Some of the info below may not be perfectly accurate, still ongoing investigative biomedical research.
"They also observed that the phase of the spontaneous circadian rhythm did not lock. This is because, circadian rhythm is very flexible. In humans, the cycle repeats about every 24.2 hours. The circadian clock is reset by light and our circadian apparatus is exquisitively sensitive to lights falling on the retina. The retina sends this light (for synchronization) to the SCN via the retino-hypothalamic tract. This synchronization or entrainment can now 'phase lock' the circadian rhythm.
Clinical implication of circadian (circa=about; dian=day) rhythm is enormous. Our sleep-wake cycle, growth hormone and cortisol secretion are only a few example. A person in whom the circadian period is short will rise early (early bird?) and a 'night owl' will have his/her circadian period short. Curiously, our sleepiness, tendency to sleep and occurrence of REM sleep peaks (resulting from endogenous circadian rhythm) when we are about to rise; and our endogenous clock reaches its peak about 1-3 hrs before our habitual bedtime.
link
Humans are the only species with exposed white sclerae.
20% of European/Asian humans sneeze at bright sunlight after having been dark-adapted. Humans can see clearly underwater (conclusively tested in Thai Moken children seafood forage divers and Scandinavian children) by employing 'visual accomodation', which is a form of dark-adaptation of the oculomotor nerve (CN#3) in association with the trigeminal nerve, the pupils constrict voluntarily, the complementary opposite of the pupillary light reflex and photic sneeze reflex, since this is not found in our mammalian kin, it must be assumed to have occurred in our seashore diving ancestors as selection for improved seafood foraging efficiency.
link
The Edinger-Westphal nucleus supplies preganglionic parasympathetic fibers to the eye, constricting the pupil and accommodating the lens. Edinger-Westphal nucleus (also known as the accessory oculomotor nucleus) is the accessory parasympathetic cranial nerve nucleus of the oculomotor nerve (cranial nerve III), supplying the constricting muscles of the iris. http://en.wikipedia.org/wiki/Edinger-Westphal_nucleus
The accommodation reflex is a reflex action of the eye, in response to focusing on a near object, then looking at distant object (and vice versa), comprising coordinated changes in vergence, lens shape and pupil size. It is dependent on cranial nerve II (afferent limb of reflex), higher centres and cranial nerve III.
http://en.wikipedia.org/wiki/Accommodation_reflex
http://en.wikipedia.org/wiki/Accommodation_(eye)
http://hyperphysics.phy-astr.gsu.edu/hbase/vision/accom.html
http://hyperphysics.phy-astr.gsu.edu/hbase/vision/accom.html#c3
http://en.wikipedia.org/wiki/Adaptation_(eye)
http://en.wikipedia.org/wiki/Pupil
When bright light is shone on the eye, it will automatically constrict. This is the pupillary reflex, which is an important test of brainstem function. Furthermore, the pupil will dilate if a person sees an object of interest.
The oculomotor nerve, specifically the parasympathetic part coming from the Edinger-Westphal nucleus, terminates on the circular iris sphincter muscle. When this muscle contracts, it reduces the size of the pupil. The pupil gets wider in the dark but narrower in light. When narrow, the diameter is three to four millimeter. In the dark it will be the same at first, but will approach the maximum distance for a wide pupil 4 to 5 mm. The constriction of the pupil and near vision are closely tied. In bright light, the pupils constrict to prevent aberrations of light rays and thus attain their expected acuity; in the dark this is not necessary, so it is chiefly concerned with admitting sufficient light into the eye. The pupil dilates in extreme psychical situations (e.g., fear) or contact of a sensory nerve, such as pain.
http://en.wikipedia.org/wiki/Miosis
"They also observed that the phase of the spontaneous circadian rhythm did not lock. This is because, circadian rhythm is very flexible. In humans, the cycle repeats about every 24.2 hours. The circadian clock is reset by light and our circadian apparatus is exquisitively sensitive to lights falling on the retina. The retina sends this light (for synchronization) to the SCN via the retino-hypothalamic tract. This synchronization or entrainment can now 'phase lock' the circadian rhythm.
Clinical implication of circadian (circa=about; dian=day) rhythm is enormous. Our sleep-wake cycle, growth hormone and cortisol secretion are only a few example. A person in whom the circadian period is short will rise early (early bird?) and a 'night owl' will have his/her circadian period short. Curiously, our sleepiness, tendency to sleep and occurrence of REM sleep peaks (resulting from endogenous circadian rhythm) when we are about to rise; and our endogenous clock reaches its peak about 1-3 hrs before our habitual bedtime.
link
Humans are the only species with exposed white sclerae.
20% of European/Asian humans sneeze at bright sunlight after having been dark-adapted. Humans can see clearly underwater (conclusively tested in Thai Moken children seafood forage divers and Scandinavian children) by employing 'visual accomodation', which is a form of dark-adaptation of the oculomotor nerve (CN#3) in association with the trigeminal nerve, the pupils constrict voluntarily, the complementary opposite of the pupillary light reflex and photic sneeze reflex, since this is not found in our mammalian kin, it must be assumed to have occurred in our seashore diving ancestors as selection for improved seafood foraging efficiency.
link
The Edinger-Westphal nucleus supplies preganglionic parasympathetic fibers to the eye, constricting the pupil and accommodating the lens. Edinger-Westphal nucleus (also known as the accessory oculomotor nucleus) is the accessory parasympathetic cranial nerve nucleus of the oculomotor nerve (cranial nerve III), supplying the constricting muscles of the iris. http://en.wikipedia.org/wiki/Edinger-Westphal_nucleus
The accommodation reflex is a reflex action of the eye, in response to focusing on a near object, then looking at distant object (and vice versa), comprising coordinated changes in vergence, lens shape and pupil size. It is dependent on cranial nerve II (afferent limb of reflex), higher centres and cranial nerve III.
http://en.wikipedia.org/wiki/Accommodation_reflex
http://en.wikipedia.org/wiki/Accommodation_(eye)
http://hyperphysics.phy-astr.gsu.edu/hbase/vision/accom.html
http://hyperphysics.phy-astr.gsu.edu/hbase/vision/accom.html#c3
http://en.wikipedia.org/wiki/Adaptation_(eye)
http://en.wikipedia.org/wiki/Pupil
When bright light is shone on the eye, it will automatically constrict. This is the pupillary reflex, which is an important test of brainstem function. Furthermore, the pupil will dilate if a person sees an object of interest.
The oculomotor nerve, specifically the parasympathetic part coming from the Edinger-Westphal nucleus, terminates on the circular iris sphincter muscle. When this muscle contracts, it reduces the size of the pupil. The pupil gets wider in the dark but narrower in light. When narrow, the diameter is three to four millimeter. In the dark it will be the same at first, but will approach the maximum distance for a wide pupil 4 to 5 mm. The constriction of the pupil and near vision are closely tied. In bright light, the pupils constrict to prevent aberrations of light rays and thus attain their expected acuity; in the dark this is not necessary, so it is chiefly concerned with admitting sufficient light into the eye. The pupil dilates in extreme psychical situations (e.g., fear) or contact of a sensory nerve, such as pain.
http://en.wikipedia.org/wiki/Miosis
Wednesday, November 5, 2008
Evolving tides
http://vimeo.com/1914765?pg=embed&sec=1914765
Magnificent Polar arctic & antarctic show and music (aria de amor (tosca))
h/t jeanie
Magnificent Polar arctic & antarctic show and music (aria de amor (tosca))
h/t jeanie
Friday, October 24, 2008
Musing on music of the seashore divers
(from my post at deeperblue.com, re. Rather than listening to conventional i-pod music during a dive...)
I think I prefer to tune in to the sounds of the sea, with the middle ear canals saline-filled to still the dissonance of air conduction against bone conduction while diving. But since I've never done this (being too cold here to try) I'll just have to wait til I get to the tropics again, if ever, to hear as a dolphin hears (in a sense) the echoes of the dive song...
listening most intently at depth while my backfloating wife/dive partner hums a lullaby to our nursing infant son and daughter at the warm sunlit surface of the tropical lagoon, she in turn listens to the water for my dental-lingual clicking, knowing I'm soon to bring up some delicious fresh seafood from the ocean's banquet. I can't think of a better harmony than that little duet...
not a mythical haunting symphony of the sailors' sirens of the seas,
nor the obnoxious cacophony of the chattering rainforest monkeys,
nor the roaring of beached sea lions or trumpeting of sea elephants,
nor the loud whoops or paired call-songs of the inland swamp apes,
just ongoing quiet baby babbling and mothers humming melodies at the surface,
and non-vocalized staccato rhythmic clicking invisible yet audible from beneath,
alternating and complementing each other, the couple's chorus of the seashore,
with the simple message, "I am here, I hear you, you are there, I'll see you soon".
with nothing but deep & clear, sky-blue waters as the superb conductor,
and colorful fish & corals, jellyfish and urchins the distinguished audience,
and dolphins, dugongs, sharks and sea turtles the occasional stagehands,
Operettas performed repeatedly, daily feasts for more than a million years,
we come from awesome beginnings.
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
[inspired by HHamid]
DDeden
___________________
The-Arc-of-a-Diver:
http://the-arc.wikispaces.com/
http://the-arc-ddeden@blogspot.com
My post at AAT on humming/sneezing/sleep apnea/prone clicking/supine humming/Nitric Oxide and suckling/etc. http://tech.groups.yahoo.com/group/AAT/message/48696
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Images
Triaxial weaving
http://www.nikonsmallworld.com/gallery.php?grouping=year&year=2008&imagepos=107
Carbon nanotubes (sponge)
http://www.nikonsmallworld.com/moreinfo.php?grouping=year&year=2008&imagepos=2
Squid embryos
http://www.nikonsmallworld.com/moreinfo.php?grouping=year&year=2008&imagepos=59
tree branching
http://www.nikonsmallworld.com/moreinfo.php?grouping=year&year=2008&imagepos=19
and finally, pass the peanuts
http://tech.groups.yahoo.com/group/AAT/message/48610
"LOLrus found the bucket"
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Breathing, Backfloating, Diving cycles
MV: Yes, little doubt our ancestors once regularly dived in clear sunlit sea-water, cf.studies on Moken (& later Scandinavian) children (pupil closure), this perfectly fits your photic sneeze idea.
Cheyne-Stokes respiration Pronunciation (chān stōks)
A rhythmical breathing where there is an alteration in the depth of the breaths and there are regularly occurring apneic episodes. The pattern of breathing with gradual increase in depth and sometimes in rate to a maximum, followed by a decrease resulting in apnea; the cycles ordinarily are 30 seconds to 2 minutes in duration, with 5–30 seconds of apnea; seen with bilateral deep cerebral hemispheric lesions, with metabolic encephalopathy, and, characteristically, in coma from affection of the nervous centers of respiration.
MV: Typical human Nasal Cycle suggests our ancestors dived for about 90".
Typical Sleep Apnea Rhythms in humans AFAIK seem to be a bit shorter 60".
Perhaps these 2 cycles synchronised, or perhaps they're remnants of different diving cycles (at different evolutionary periods possibly).
MV: The erectile tissue in vasomotor rhinopathy, allergic rhinitis ("hay fever"), etc.
The nasal cycle is ca.90 seconds. A periodicity of 90 seconds: for what purpose other than diving? Flaring of the nostrils is more anteriorly, at the nose entrance, not
inside the nose at the conchas, where the erectile tissue is.
MV: A lot of people suffer from nasal obstruction (by swelling of venous caverns over the inferior concha - uniquely human): can be complete, more frequent when lying down, see my paper "AAT & some common diseases". An important argument is that there's a nasal cycle in this swelling with a periodicity of c 90 seconds.
MV: Streamlining is extremely important for any actively moving (even slow-moving) animals: water is ~800 times denser than air, and ~60 times more viscous, so streamlining saves a lot of energy for the time they spent in water diving for seafoods.
MV: In Cetacea, the time needed to breathe is a few seconds or less,
DD: Yes. However, this depends on species, diving depth, diving length,
feeding behaviour, size, typical speed in water, association with other intra-specifics (competition, co-op.). There is some variability, like Homo.
MV: but our nasal cycle (about 90", Paul Van Cauwenberge) seems to suggest that our ancestors dived & floated (cf. sea otters) for about half of that time, so perhaps spouting was not necessary?
DD: Spouting depends on length of time sub-surface, not at-surface time.
I think it's likely they sneeze-spouted while surfacing from long deep
dives, whereas shallow swimming dives might have been more voluntary
blowing (seems like seals use this in shallows).
MV: The usual cycle in sleep apnea syndrome is shorter (almost a minute), so there might have been different diving customs (in different phases? or could the cycles be synchronised & used at the same time?)
DD: Perhaps different time cycles reflect different diving-depths, or
different evolutionary periods (freshwater-river vs. marine) or simply
variation due to lack of use more recently, (do vestigial organs
(tailbone-muscles, ribs, adenoids, vestigial veins) vary in shape-size
in modern Homo? I think there is much variety, considering the genetic
bottlenecks of modern HS).
DD: I currently (speculatively) view the diving-breathing cycle as a Homo aquaticus complete package, with most of the cycles in synchrony, (even possibly in synchrony with menstruation, lunar tide, sunspots, whatever).
MV: but this again suggests they stayed at the surface for almost half a minute or so.
DD: Possibly, the larger the mammal, the more explosive the exhalation? Elephants have unusual lungs, explained by their snorkel-trunk, but also possibly due to long-time submergence as well.
MV: As for the (lack of) basicranial flexion in He, if the face/nose was upwards, the body must perhaps have been vertical I'd think.
DD: What would be the largest angle they could comfortably backfloat? I drew it at 90 degrees (sea otters and modern Hs can backfloat at 90 degrees comfortably), you are suggesting 180 degrees when surfacing. Would they backfloat with eyes closed and submerged, or eyes above water? Nostrils may have remained sealed at surface (philtrum-septum valve) while mouth breathing, or alternatively, mouth closed (eating)while nostrils were open above surface.
MV: I suppose they emerged with vertical body & with the nostrils first, so I don't think they spouted in a horizontal position.
DD: Likely more forward position then, perhaps 45 degrees, (sperm whales, some balleens, sirenians?, walrus?).
MV: Did they spout through the mouth (as you drew it) or the nose or both
IYO? IYO the spouting = sneezing?
MV: Our aquarboreal theory: I tend to think early hominoids (suspension in trees) must have swum regularly [DD: face always above water, laryngeal air sacs inflated], eg, to get at the trees of other islands in the Tethys, but not that they dived a lot (although it's difficult to exclude the possibility). Wading came later IMO (early hominids, ie, even after the hominid/pongid split?). Regular diving only in Homo (although, again, earlier periods of diving can't be excluded). An external nose suggests partial aq. adapations (full aquatics have no external noses), and all apes lack this feature (I'm not sure about prenatal stages).
MV: From "The aquatic ape theory: evidence and a possible scenario" Med.Hypoth.16:17-32, 1985: "Intranasal adaptations - All aquatic mammals are able to close the nostrils, and they do so under water. Most terrestrial mammals cannot close their nostrils. Humans have rudimentary compressor and dilatator naris muscles. An even better "nose-closing-system" in our ancestors could have been the erectile tissue of the inferior nasal concha with its uniquely [not present in other mammals AFAWK, eg, not in chimps] abundant and hypersensitive plexus cavernosus. In humans, a very sudden and complete nasal obstruction can be caused by sudden changes in humidity or temperature, e.g. going into the water, or even by laying down
(vasomotor rhinopathy). Moreover, humans have a short cycle of non-alternating fluctuations in nasal resistance: the erectile tissues of the conchae involuntarily swell and shrink with a rhythm of 90 sec (23). This corresponds to the diving-rhythm of the diving women of Korea and Japan (3). In shallow-diving aquatic endotherms, the diving-and-emerging cycle is usually less than 3 min. Enhydra, for example, dives for 30 to 40 sec to catch a few mussels or sea-hedgehogs, and then emerges and floats on the surface for about the same time to crack and eat them (see Stage III)." I still think it's correct, although I would now formulate it more cautiously...
MV: It's true that salt water (eg, sterilised sea water) can well be used to clear the nasal passages (not the sinuses): salt water (more than fresh or even physiologic water?) seems to have some decongestive effect on the nasal mucosa.
DD: What is cause of vasomotor rhinopathy? bacteria, virus, genetic?
MV: Hyperactive erectile tissue on inferior concha, often elicited by laying down, or by cold & wet weather (= the reason why viral rhinitis is often called "a cold" (common cold): it resembles vasomotor rhinopathy (but has more more rhinorrhea - allergic rhinits has more sneezing & itching).
MV: The inferior concha is the lower turbinal (I think "turbinal" & "turbinate" are interchangeable): scroll-like, thin, bony processes lined throughout by mucous membrane on the lateral walls & roof of the nasal cavity, which form a labyrinth of so-called turbinals or conchae (Schultz 1969:141). Haplorhini have less turbinals than Strepsirhini, and the olfactory epithelium is withdrawn to the remotest uppermost region, eg, adult hominids-pongids only have 3 conchae (inf.=maxillo-turbinal, middle=endoturb.I, sup.=endoturb.II); gibbons & monkeys usu.still have the naso-turbinal (uppermost turbinal) = rudimentary "agger nasi" in hominids-pongids; "early in the life of man there are still as many as 5 ethmo-turbinals laid down besides the maxillo-& naso-turbinals" (7!).
DD: Does/can Vasomotor Rhinopathy occur both in sea and freshwater?
MV: It occurs on land, of course, but I don't have the impression it's more frequent when I go swimming. Everybody (incl.non-VR patients) seems to have it to some extent: it has a (uniquely human?) nasal cycle of about 90 seconds (dry apers usu.confuse this with the "long" nasal "cycle" (also in other mammals) which is perhaps fifty times longer, and not in both conchae at the same time) with which both inferior conchae synchronously swell & shrink. The only reasonable explanation I can find for such a cycle is cyclic diving, but possibly not in the latest pre-terrestrial phase (otherwise it would have been more functional in us today when we dive I'd think).
DD: Does/can VR occur both in warm (blood temp.) and cold water?
MV: Most VR patients have more problems in misty weather.
DD: Does/can VR occur both in shallow and very deep water? Does/can VR occur
both in Vt. Head up & Head down, Hz. position?
MV: Most patients have more problems at night (horizontal position, but nobody sleeps with his head down). When we lay down on our right side, it's usu.the right nasal passage that is blocked, and v.v. This happens almost immediately. It gradually worsens by abuse of nasodilator drops (Nesivin etc.).
DD: Does/can VR occur both in active swimming and inactive sinking-diving?
MV: Yes, but AFAIK there are no studies on this.
DD: [Closeable nostrils/nares prevent water from entering nasal cavities, you are saying the same applies to VR. Could water enter the paranasal sinuses or any part of the nasal cavity if the erectile tissues are fully erected?
MV: No, the nose is completely blocked, as any VR patient can tell you (it's very frequent).
DD: Do newborns/infants/children/adults all have VR capability?
MV: To some extent, probably yes. About 10-15 years ago (when I read a lot about this), one of the few groups worldwide that studied the (short) nasal cycle was that of prof. Van Cauwenberghe from Univ.Gent (now rector of the university). IIRC he told me that the cycle is more prevalent in children than in adults. Since newborns are obligate nose-breaters, I guess they don't have it (and, see Schultz above ("early in life"=?), they still have more than 3 conchae!).
DD: Are there semi-aquatic animals that use VR in diving?
MV: AFAIK, it's unuquely human. Cetacea have special pump systems that immediately block the nasal passages, but you can hardly compare these to our nasal swelling tissue.
DD: Cetaeceans inhale 3,000 times more air than Hs in 1/2 the time a Hs takes. -Humans exchange 15% of the air we breathe normally (NOT PS), Ceteaceans an exchange 85-90% of their air (How? Sneeze?) -During sneeze, how much air is exchanged? [Critical question] -The diving reflex depends on max. temp. differential, PS does not. -PS depends on max. light differential, diving reflex does not. -Speculation: Cetae (esp. large deep whales) have a
baro-sensor or temperature-sensor which triggers exhale (sneeze IMO) through
blowhole, most likely the sensor is part of the ear or eye region, though possibly part of the blowhole or echolocation equipment. -PS is semi-voluntary in Hs, often can be delayed if necessary. -PS only occurs after in-dark for about a minute.
MV: Is this so, DD?
DD: No. Not absolute, but I've read 4-5 minutes (I doubt this was timed scientifically). [The synovial fluid in finger knuckle joints can "pop", then can't be popped for about 15 minutes, this was timed scientifically.] I don't think the PS was timed this way, and from my own experience, can happen more often than 1 time in 4 minutes. My guess is that if it was done
habitually as part of a diving respiratory cycle, it would be about 1.5 to 2.5 minutes. In modern Hs, it is variable. Problem: at 200 ft down, light is 5% visible in perfect clear seawater, but if they only dived to 50ft, too much light, no PS?
MV: The best moment to sneeze would have been at the exact moment of emerging.
If surfacing-sneezing ever existed, the exact moment must have been fine-tuned by different means: sunlight ("photic") would indeed be a good indicator I'd think, but also some CNS urge to sneeze at emerging (CO2, O2?), and perhaps cutaneous sensory afferents?
DD: -Sneezing can be done vert. or horiz., probably not underwater.
MV: When a mammal starts diving (eg, to collect underwater shellfish), it has to keep the water out of its airways by all means. This can be achieved, eg, by lengthening of the airways, by narrowing them, by evolving closure possibilities... (= in parallel). We see all of this in human ancestors: external nose, longer internal airway (can be seen on transection of human & chimp nasal cavity), cavernous venous sinuses over inferior conchae, splitlike nostrils, nostril closure in young children, upper lip + philtrum to close nostrils, perhaps velum to close posterior nares. I assume that when diving becomes perfected, only one of these remains necessary.
MV: Bronchial hyper-reactivity as well as bronchial sphincters are typical of
humans (asthma) & also of, eg, seals (Elaine "Aq.ape" p.89). - allergy: Some people have stronger IgE allergic reactions than others. I don't know whether humans are generally more allergic than apes?
MV: The nose was closed: at the nostrils & at the cavernous tissue on the conchae & at the velum. The mouth could be closed at the lips & the tongue, voluntarily (BTW, this is how we voluntarily can produce consonants at free will at different places (labial, dental etc., ie, the beginning of human speech): according to suction & eating underwater. During swallowing the larynx was closed by the epiglottis. I can't see any parallelism/convergence here between dolphins & us. Cetacea have ascended larynges, the opposite of Hs. Besides, the pressure upon the glottis would have been far too high. The vocal chords (very fine & mobile structures) are for phonation, not for closing the airways underwater. This was done by the tongue & the epiglottis.
Laryngospasm is a reflex also seen in terr.mammals, to protect against food, fluids, insects... falling/flying into the airways. Of course, they closed when water came in, but not or at least not in the first place because we were semi-aquatic.
MV: - There is a so-called "long" cycle, ill-defined, about 1 to 4 hours, a general fluctuation of the nasal passages, usu.alternating right & left, not typically human. (I guess it has to do with olfaction or with cleansing of the nasal passages?)
- There is a typically-human "short" cycle of ~90 seconds, in which both nasal passages at the same time narrow by swelling of the venous plexus on the inferior nasal concha. I have no doubt this has to do with diving. At the time I corresponded with one of the investigators of this cycle,
prof. Paul van Cauwenberge (now rector of the University of Ghent), who knows what he's talking about. These swelling tissues (comparable to the corpora cavernosa in the penis) are activated by lying down, by sudden cooling & by misty weather (cf. going into the water?) - the reason why "common cold" (in fact, a viral infection by rhinoviruses of the upper airways) is often thought to be caused by "cold". People who suffer a lot from this common condition have "vasomotor rhinitis" (nasal obstruction due to swelling of the veins of the lower concha, ofter made worse by abusus of nasal vasocontrictors). It's the same swelling tissue that is often stimulated in allergic people (eg, pollen allergy).
MV: When a terrestial mammal finds more & more food underwater, it has to dip or dive for it, and therefore to close its airways underwater. Every adaptation that helps to close the airways will be advantageous during these early adaptations to food collection underwater: H as compared to P have longer airways, an external nose, the nostrils underneath the nose, an
inverted U in the nasal passage, narrower airways, swelling tissues on the inferior concha, an upper lip that can seal off the nostrils, nostril-closing muscles, etc.
MV: Interesting is that we seem to have 2 diving cycles: one at the conchae of ~90", and one during SAS (sleep apena syndrome) of ~60" or so. This seems to suggest that our diving habits showed at least 2 different phases?
ice age increases aquaticness?
Wet sinuses, VR, venal pooling at depth, bronchial closure... http://tech.groups.yahoo.com/group/AAT/message/38976
http://tech.groups.yahoo.com/group/AAT/message/39630
Clicking
http://tech.groups.yahoo.com/group/AAT/message/40072
Archaic pre-heidelbergensis calvaria at Ceprano Italy
http://scienceblogs.com/afarensis/2008/11/02/sunday_need_to_read_more_from/
http://www.citeulike.org/user/EsepBib/article/1122446
Common descent @ Dive Song
http://tech.groups.yahoo.com/group/AAT/message/41529
DD: Why do we sneeze, which is a complex, whole body reaction, only to remove microscopic pollen, when simply blowing the nose is more effective and more efficient? If sneezing is to remove particles, then why do people often blow their nose AFTER sneezing? And why the runny nose AFTER sneezing, if the particles are supposedly removed already? It just does not add up to natural selection for fitness.
MV: Rhinorrhea can be caused allergic reaction, viral damage &/or anti-viral reaction (rinsing away viruses/allergens)? They overlap, but generally allergy = more sneezing, VR = more obstruction, common cold (rhinoviruses) = more rhinorrhea.
Ice Age - Aquaticness effects
=====================================================
m3d: While back floating the face/mouth would out of the water, but the ears would be in the water, would you hear a clicking/humming sound emitted above the surface of the water?
DD: Sound moves about 1500 meters per second in seawater. Sound moves much more slowly in air, at about 340 meters per second. Note that both prone clicking at depth and supine humming at surface both produce sound underwater. Humming while exhaling sends sounds out of the nostrils or both nostrils and mouth which are above the water surface, however the sound is actually produced in the larynx at the glottal folds which is submersed, like the ears, while backfloating.
This means for example the infant nursing on the mother hears the air-born sound (laryngeal-nasal humming or laryngeal-oral song), while the partner below hears primarily the water-born laryngeal vibration of the humming but perhaps not any verbal consonants. One possible reason why humans don't have SC fat covering the throat especially around the adams apple may be because it would weaken (insulate) the hum/song/speech) sound transmission.
Submerged prone clicking, due to it's open mouth (bell jar) method, would travel directly from the air entrapped oral cavity to the water, without skin or fat to obstruct or insulate the sound. Therefore the chubby cheeks did not interfere with click sound transmissions. (That had confused me earlier, when trying to click with closed mouth.)
So apparently human ancestors at seashores used these: underwater open mouth clicking, supine humming in eupnea with nursing infant, clear vision at dark depth followed by whalespout sun sneezing, sunwarmed catnaps while backfloating in apnea.
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Am J Physiol Regul Integr Comp Physiol. 2008 Nov 5.
Repetitive paired stimulation of nasotrigeminal and peripheral chemoreceptor afferents cause progressive potentiation of the diving bradycardia.
Rozloznik M, Paton JF, Dutschmann M. Neuro and Sensory Physiology, Georg-August University Goettingen, Goettingen, Germany.
The hallmarks of the mammalian diving response are protective apnea and bradycardia. These cardio-respiratory adaptations can be mimicked by stimulation the trigeminal ethmoidal nerve (EN5) and reflect oxygen conserving mechanisms during breath-hold dives. Increasing drive from peripheral chemoreceptors during sustained dives was reported to enhance the diving bradycardia. The underlying neuronal mechanisms, however, are unknown. In the present study, expression and plasticity of EN5-bradycardias after paired stimulation of the EN5 and peripheral chemoreceptors was investigated in the in situ working heart-brainstem preparation. Paired stimulations enhanced significantly the bradycardic responses compared to EN5-evoked bradycardia using sub-maximal stimulation intensity. Alternating stimulations of the EN5 followed by paired stimulation of the EN5 and chemoreceptors (10 trials, 3 min interval) caused a progressive and significant potentiation of EN5-evoked diving bradycardia. In contrast, bradycardias during paired stimulation remained unchanged during repetitive stimulation. The progressive potentiation of EN5-bradycardias was significantly enhanced after microinjection of the 5-HT3 receptor agonist (CPBG hydrochloride) into the nucleus tractus solitarii (NTS), while the 5-HT3 receptor antagonist (zacopride hydrochloride) attenuated the progressive potentiation. These results suggest an integrative function of the NTS for the multi-modal mediation of the diving response. The potentiation or 'training' of a sub-maximal diving bradycardia requires peripheral chemoreceptor drive and involves neurotransmission via 5-HT3R within the NTS. Key words: diving response, plasticity, nucleus of the solitary tract.
Electrical stimulation of the anterior ethmoidal nerve produces the diving response
Paul F. McCulloch*, Kevin M. Faber and W. Michael Panneton
Department of Anatomy and Neurobiology, Saint Louis University School of Medicine, 1402 South Grand Blvd., St. Louis, MO 63104, USA Accepted 9 March 1999.
Stimulation of the upper respiratory tract usually produces apnea, but it can also produce a vagally mediated bradycardia and a sympathetically mediated increase in peripheral vascular resistance. This cardiorespiratory response, often called the diving response, is usually initiated by nasal stimulation. The purpose of this research was to investigate the anterior ethmoidal nerve (AEN) that innervates the nasal mucosa of muskrats (Ondatra zibethicus). Electrical stimulation of the AEN (typically 50 Hz, 100 μs and 500 μA) produced immediate and sustained bradycardia and cessation of respiration similar to that of the diving response. Heart rate (HR) significantly decreased from 264±18 to 121±8 bpm, with a concurrent 4.2±0.9 s apnea, during the 5 s stimulation period. BP decreased from 97.9±4.8 to 91.2±6.4 mmHg. Using estimations from (1) cross-sectional areas of AEN trigeminal ganglion cells labeled with WGA-HRP, and (2) electron microscopic analysis of the AEN, we found that approximately 65% of the AEN is composed of unmyelinated C-fibers. In addition, 72.4% of myelinated fibers from the nerves that innervate the nasal passages were of small diameter (<6 n="1142">50 s). DMR decreased by 15%, but did not differ significantly from surface metabolic rates (MR(S)) when dive duration increased from 1 to 7 min. Overall, these data suggest that DMR is almost the same as MR(S), and that Steller sea lions incur an O(2) debt during spontaneous diving that is not repaid until the end of the dive bout. This has important consequences in differentiating between the actual and ;apparent' metabolic rate during diving, and may explain some of the differences in metabolic rates reported in pinniped species.
Respir Physiol Neurobiol. 2008 Oct 9.
Estimating the effect of lung collapse and pulmonary shunt on gas exchange during breath-hold diving: The Scholander and Kooyman legacy. Fahlman A, Hooker SK, Olszowka A, Bostrom BL, Jones DR.
Global Diving Research, Ottawa, ON, Canada K2J 5E8; Department of Zoology, The University of British Columbia, 6270 University Blvd., Vancouver, BC, Canada V6T 1Z4.
We developed a mathematical model to investigate the effect of lung compression and collapse (pulmonary shunt) on the uptake and removal of O(2), CO(2) and N(2) in blood and tissue of breath-hold diving mammals. We investigated the consequences of pressure (diving depth) and respiratory volume on pulmonary shunt and gas exchange as pressure compressed the alveoli. The model showed good agreement with previous studies of measured arterial O(2) tensions ( [Formula: see text] ) from freely diving Weddell seals and measured arterial and venous N(2) tensions from captive elephant seals compressed in a hyperbaric chamber. Pulmonary compression resulted in a rapid spike in [Formula: see text] and arterial CO(2) tension, followed by cyclical variation with a periodicity determined by Q (tot). The model showed that changes in diving lung volume are an efficient behavioural means to adjust the extent of gas exchange with depth. Differing models of lung compression and collapse depth caused major differences in blood and tissue N(2) estimates. Our integrated modelling approach contradicted predictions from simple models, and emphasised the complex nature of physiological interactions between circulation, lung compression and gas exchange. Overall, our work suggests the need for caution in interpretation of previous model results based on assumed collapse depths and all-or-nothing lung collapse models.
Cheetahs of the deep sea: deep foraging sprints in short-finned pilot whales off Tenerife (Canary Islands)
Authors: Aguilar Soto, Natacha; Johnson, Mark P.; Madsen, Peter T.; Díaz, Francisca; Domínguez, Iván; Brito, Alberto; Tyack, Peter
Source: Journal of Animal Ecology, Volume 77, Number 5, September 2008 , pp. 936-947(12) Publisher: Blackwell Publishing
Summary: Empirical testing of optimal foraging models for breath-hold divers has been difficult. Here we report data from sound and movement recording DTags placed on 23 short-finned pilot whales off Tenerife to study the foraging strategies used to catch deep-water prey. Day and night foraging dives had a maximum depth and duration of 1018 m and 21 min. Vocal behaviour during dives was consistent with biosonar-based foraging, with long series of echolocation clicks interspersed with buzzes. Similar buzzes have been associated with prey capture attempts in other echolocating species.
Foraging dives seemed to adapt to circadian rhythms. Deep dives during the day were deeper, but contained fewer buzzes (median 1), than night-time deep dives (median 5 buzzes). In most deep (540-1019 m) daytime dives with buzzes, a downward directed sprint reaching up to 9 m s−1 occurred just prior to a buzz and coincided with the deepest point in the dive, suggestive of a chase after escaping prey.
A large percentage (10-36%) of the drag-related locomotion cost of these dives (15 min long) is spent in sprinting (19-79 s). This energetic foraging tactic focused on a single or few prey items has not been observed previously in deep-diving mammals but resembles the high-risk/high-gain strategy of some terrestrial hunters such as cheetahs. Deep sprints contrast with the expectation that deep-diving mammals will swim at moderate speeds optimized to reduce oxygen consumption and maximize foraging time at depth. Pilot whales may have developed this tactic to target a deep-water niche formed by large/calorific/fast moving prey such as giant squid.
Heart rate and blood pressure time courses during prolonged dry apnoea in breath-hold divers
Authors: Perini, Renza1; Tironi, Adelaide2; Gheza, Alberto2; Butti, Ferdinando2; Moia, Christian3; Ferretti, Guido2
Source: European Journal of Applied Physiology, Volume 104, Number 1, September 2008 , pp. 1-7(7) Publisher: Springer
To define the dynamics of cardiovascular adjustments to apnoea, beat-to-beat heart rate (HR) and blood pressure and arterial oxygen saturation (SaO2) were recorded during prolonged breath-holding in air in 20 divers. Apnoea had a mean duration of 210 ± 70 s. In all subjects, HR attained a value 14 beats min−1 lower than control within the initial 30 s (phase I). HR did not change for the following 2-2.5 min (phase II). Then, nine subjects interrupted the apnoea (group A), whereas 11 subjects (group B) could prolong the breath-holding for about 100 s, during which HR continuously decreased (phase III). In both groups, mean blood pressure was 8 mmHg above control at the end of phase I; it then further increased by additional 12 mmHg at the end of the apnoea. In both groups, SaO2 did not change in the initial 100-140 s of apnoea; then, it decreased to 95% at the end of phase II. In group B, SaO2 further diminished to 84% at the end of phase III. A typical pattern of cardiovascular readjustments was identified during dry apnoea. This pattern was not compatible with a role for baroreflexes in phase I and phase II. Further readjustment in group B may imply a role for both baroreflexes and chemoreflexes. Hypothesis has been made that the end of phase II corresponds to physiological breakpoint.
Undersea Hyperb Med. 2008 May-Jun;35(3):163-7.
Barotraumatic orbital emphysema of rhinogenic origin in a breath-hold diver: a case report. Bolognini A, Delehaye E, Cau M, Cosso L. Sardinian Institute of Hyperbaric and Subaquatic Medicine, Sassari, Italy.
Orbital emphysema is a well-recognized complication of fractures involving the orbit. Commonly, it occurs when high pressure develops in nasal cavity as during nose blowing, coughing or Valsalva's maneuver and usually occurs in the subcutaneous tissues. We report the case of a young breath-hold diver who developed spontaneous, non compressive orbital emphysema during underwater fishing, with a maximal depth of 25-30 meters in the Sardinian sea. He was otherwise healthy, without previous cranio-facial trauma and nasosinusal diseases or surgery were not present in the history. When he was referred to our attention the patient presented right eyelid ptosis but diplopia and vision impairment were absent. Computer tomography scans showed subcutaneous air in the right upper eyelid and around the eyeball, particularly near the orbit's roof but optic nerve area, intraconal, was free of air. A dehiscence in lamina papyracea was evident. In our opinion, this has been the point of air entry into the orbit. A supportive therapy was advised and two weeks later the emphysema was recovered completely and the subject was symptoms free. The literature has been revised and to our knowledge no previous cases of barotraumatic orbital emphysema, in a breath-hold diver, are referred.
J Comp Physiol [B]. 2008 Nov 5.
Terrestrial apnoeas and the development of cardiac control in Australian fur seal (Arctocephalus pusillus doriferus) pups.
Deacon NL, Arnould JP. School of Life and Environmental Sciences, Deakin University, 221 Burwood Highway, Burwood, VIC, 3125, Australia.
The development of cardiac control in association with terrestrial respiration patterns was examined throughout the period of maternal dependence in Australian fur seal pups. Resting eupnoic heart rate and respiration rate were significantly correlated (r (2) = 0.49) and both decreased with age (P < href="http://news.bbc.co.uk/2/hi/science/nature/7358868.stm">http://news.bbc.co.uk/2/hi/science/nature/7358868.stm
A humid corridor across the Sahara for the migration of early modern humans
out of Africa 120,000 years ago AH Osborne cs 2008 PNAS 105:16444-7
It is widely accepted that modern humans originated in sub-Saharan Africa 150-200 thousand years ago (ka), but their route of dispersal across the currently hyperarid Sahara remains controversial. Given that the first modern humans north of the Sahara are found in the Levant 120-90 ka, northward dispersal likely occurred during a humid episode in the Sahara within Marine Isotope Stage (MIS) 5e (130-117 ka). The obvious dispersal route, the Nile, may be ruled out by notable differences between archaeological finds in the Nile Valley and the Levant at the critical time. Further west, space-born radar images reveal networks of now-buried fossil river channels that extend across the desert to the Mediterranean coast, which represent alternative dispersal corridors. These corridors would explain scattered findings at desert oases of Middle Stone Age Aterian lithic industries with bifacial and tanged points that can be linked with industries further to the east and as far north as the Mediterranean coast. Here we present geochemical data that demonstrate that water in these fossil systems derived from the south during wet episodes in general, and penetrated all of the way to the Mediterranean during MIS 5e in particular. This proves the existence of an uninterrupted freshwater corridor across a currently hyperarid region of the Sahara at a key time for early modern human migrations to the north and out of Africa. http://news.bbc.co.uk/2/hi/science/nature/7668250.stm
Previous data show there was increased rainfall across the southern part of the Sahara between 130,000 and 170,000 years ago; in a gap between Ice Ages known as the last interglacial period.
J Trapani 2008 JHE 55:521-530
The late Quaternary Kibish Fm preserves environments reflecting a history of fluctuations in the level of nearby Lake Turkana over the past 200 ky. The Kibish Fm has yielded a diverse mammalian fauna (+ birds & crocodiles), stone tools, & the oldest anatomically modern Hs. Fish, the most common vertebrate fossils in this unit, are reported in this study. Catfish (esp.clariids & Synodontis) & Nile perch Lates niloticus predominate, but the gymnarchid Gymnarchus, a cyprinid (Barbus), tigerfish (Hydrocynus) , pufferfish (Tetraodon) & other catfish are also present. In total, 9 teleost genera are found in the Kibish Fm, representing a subset of
the 37 genera that constitute the modern Omo-Turkana ichthyo-fauna. Several taxa present in the modern fauna, incl.Polypterus & members of Cichlidae, are not found in the Kibish deposits. Most spms are preserved as disarticulated or broken skeletal elements, but some preservation of articulated elements (eg, sets of vertebrae, crania with lower jaws or cleithra) also occurs. Many of the catfish and Nile perch spms are larger than the largest reported from the modern river or lake. Faunas of Kibish Members I & III closely resemble one another; the fauna from Member IV contains only the 3 most common taxa (Clarias, Synodontis, Lates), though
this may result from insufficient sampling. Barbed bone points have been collected from the upper part of the fm, indicating a long association (200ka? 40ka?) between the human inhabitants & the fish fauna of the Omo Valley.
Stewart suggests that the hominid fishers would not have needed elaborate harpoons, fishhooks or other fishing paraphernalia : hyenas, leopards, baboons & other mammals occasionally catch fish without the benefit of technology. And traditional African fishers today sometimes
scoop fish up by hand. Several common African freshwater fish are easy to catch, esp.at certain
times of year. The best catching times would have been when fish congregated to spawn in shallow water during the rainy season, and when they were stranded in pools during the dry season : fat reserves in some fish increase towards the end of the dry season, just before spawning, which makes them esp. nutritious. Only at rel. recent African sites dating up to 50 ka have fish bones been considered as evidence that fish were an important seasonal food. Fish remains have been recorded from several early hominid sites, among them E. & W.Turkana in Kenya, Senge in Zaire, Olduvai Gorge in Tanzania, eg, at Olduvai Gorge, >4000 fragments of fish bone (catfish or Tilapia) were recovered from deposits ass.x H.habilis or the later H.erectus. The hominids lived close to a shallow, saline, alkaline lake.
http://www.nyu.edu/gsas/dept/anthro/disotell/vitae.html paper on mol. clock
Divergence dates
- Homo-Pan 6.0 Ma,
- Pongo-hominines 14.0 Ma,
- hominoid/cercopithe coid 23.0 Ma.
Because a uniform mol.clock does not fit the catarrhine mtDNA data, we
estimated divergence dates using a penalized likelihood & a Bayesian method
(both take into account the effects of rate differences on lineages),
phylogenetic tree structure & multiple calibration points.
The penalized likelihood method applied to the coding regions of the mtDNA
genome yielded the following divergence date estimates:
- cercopithecine- colobine 16.2 Ma (14.4-17.9),
- colobin-presbytin, 10.9 Ma (9.6-12.3),
- cercopithecin- papionin, 11.6 Ma (10.3-12.9),
- Macaca-Papio, 9.8 Ma (8.6-10.9).
Within the hominoids :
- hylobatid-hominid 16.8 Ma (15.0-18.5),
- Gorilla-Homo+ Pan 8.1 Ma (7.1-9.0),
- Po. py. pygmaeus-Po.py. abelii 4.1 Ma (3.5-4.7),
- Pan troglodytes- paniscus 2.4 Ma (2.0-2.7).
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technology
(from plucking, nut cracking, oyster shelling, nest weaving)
from simple to complex craft
stone simple (hand axe)
pebble + chop outside -> sharp core + chips
stone/bone complex
punching maul/awl, hafted axe/adze
wood simple (dugout canoe)
hollow log + chop inside -> dugout + chips
wood complex
dugout + adze -> thin side planks, lighter boat portage
fiber simple
strips + bundle/braid/weave -> nest, mattress
fiber complex
basket, basket boat, tri axial weave, knotted net
pelt simple
fur/skin/rawhide + deflesh/defat -> fur cape
pelt complex
cape + punch/sew -> leather clothes, skin boats
Stone - detach to create, attach hafting
Wood - detach to create, attach planking
Fiber - attach to create
Pelt - detach to create, attach sewing
I think I prefer to tune in to the sounds of the sea, with the middle ear canals saline-filled to still the dissonance of air conduction against bone conduction while diving. But since I've never done this (being too cold here to try) I'll just have to wait til I get to the tropics again, if ever, to hear as a dolphin hears (in a sense) the echoes of the dive song...
listening most intently at depth while my backfloating wife/dive partner hums a lullaby to our nursing infant son and daughter at the warm sunlit surface of the tropical lagoon, she in turn listens to the water for my dental-lingual clicking, knowing I'm soon to bring up some delicious fresh seafood from the ocean's banquet. I can't think of a better harmony than that little duet...
not a mythical haunting symphony of the sailors' sirens of the seas,
nor the obnoxious cacophony of the chattering rainforest monkeys,
nor the roaring of beached sea lions or trumpeting of sea elephants,
nor the loud whoops or paired call-songs of the inland swamp apes,
just ongoing quiet baby babbling and mothers humming melodies at the surface,
and non-vocalized staccato rhythmic clicking invisible yet audible from beneath,
alternating and complementing each other, the couple's chorus of the seashore,
with the simple message, "I am here, I hear you, you are there, I'll see you soon".
with nothing but deep & clear, sky-blue waters as the superb conductor,
and colorful fish & corals, jellyfish and urchins the distinguished audience,
and dolphins, dugongs, sharks and sea turtles the occasional stagehands,
Operettas performed repeatedly, daily feasts for more than a million years,
we come from awesome beginnings.
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[inspired by HHamid]
DDeden
___________________
The-Arc-of-a-Diver:
http://the-arc.wikispaces.com/
http://the-arc-ddeden@blogspot.com
My post at AAT on humming/sneezing/sleep apnea/prone clicking/supine humming/Nitric Oxide and suckling/etc. http://tech.groups.yahoo.com/group/AAT/message/48696
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Images
Triaxial weaving
http://www.nikonsmallworld.com/gallery.php?grouping=year&year=2008&imagepos=107
Carbon nanotubes (sponge)
http://www.nikonsmallworld.com/moreinfo.php?grouping=year&year=2008&imagepos=2
Squid embryos
http://www.nikonsmallworld.com/moreinfo.php?grouping=year&year=2008&imagepos=59
tree branching
http://www.nikonsmallworld.com/moreinfo.php?grouping=year&year=2008&imagepos=19
and finally, pass the peanuts
http://tech.groups.yahoo.com/group/AAT/message/48610
"LOLrus found the bucket"~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Breathing, Backfloating, Diving cycles
MV: Yes, little doubt our ancestors once regularly dived in clear sunlit sea-water, cf.studies on Moken (& later Scandinavian) children (pupil closure), this perfectly fits your photic sneeze idea.
Cheyne-Stokes respiration Pronunciation (chān stōks)
A rhythmical breathing where there is an alteration in the depth of the breaths and there are regularly occurring apneic episodes. The pattern of breathing with gradual increase in depth and sometimes in rate to a maximum, followed by a decrease resulting in apnea; the cycles ordinarily are 30 seconds to 2 minutes in duration, with 5–30 seconds of apnea; seen with bilateral deep cerebral hemispheric lesions, with metabolic encephalopathy, and, characteristically, in coma from affection of the nervous centers of respiration.
MV: Typical human Nasal Cycle suggests our ancestors dived for about 90".
Typical Sleep Apnea Rhythms in humans AFAIK seem to be a bit shorter 60".
Perhaps these 2 cycles synchronised, or perhaps they're remnants of different diving cycles (at different evolutionary periods possibly).
MV: The erectile tissue in vasomotor rhinopathy, allergic rhinitis ("hay fever"), etc.
The nasal cycle is ca.90 seconds. A periodicity of 90 seconds: for what purpose other than diving? Flaring of the nostrils is more anteriorly, at the nose entrance, not
inside the nose at the conchas, where the erectile tissue is.
MV: A lot of people suffer from nasal obstruction (by swelling of venous caverns over the inferior concha - uniquely human): can be complete, more frequent when lying down, see my paper "AAT & some common diseases". An important argument is that there's a nasal cycle in this swelling with a periodicity of c 90 seconds.
MV: Streamlining is extremely important for any actively moving (even slow-moving) animals: water is ~800 times denser than air, and ~60 times more viscous, so streamlining saves a lot of energy for the time they spent in water diving for seafoods.
MV: In Cetacea, the time needed to breathe is a few seconds or less,
DD: Yes. However, this depends on species, diving depth, diving length,
feeding behaviour, size, typical speed in water, association with other intra-specifics (competition, co-op.). There is some variability, like Homo.
MV: but our nasal cycle (about 90", Paul Van Cauwenberge) seems to suggest that our ancestors dived & floated (cf. sea otters) for about half of that time, so perhaps spouting was not necessary?
DD: Spouting depends on length of time sub-surface, not at-surface time.
I think it's likely they sneeze-spouted while surfacing from long deep
dives, whereas shallow swimming dives might have been more voluntary
blowing (seems like seals use this in shallows).
MV: The usual cycle in sleep apnea syndrome is shorter (almost a minute), so there might have been different diving customs (in different phases? or could the cycles be synchronised & used at the same time?)
DD: Perhaps different time cycles reflect different diving-depths, or
different evolutionary periods (freshwater-river vs. marine) or simply
variation due to lack of use more recently, (do vestigial organs
(tailbone-muscles, ribs, adenoids, vestigial veins) vary in shape-size
in modern Homo? I think there is much variety, considering the genetic
bottlenecks of modern HS).
DD: I currently (speculatively) view the diving-breathing cycle as a Homo aquaticus complete package, with most of the cycles in synchrony, (even possibly in synchrony with menstruation, lunar tide, sunspots, whatever).
MV: but this again suggests they stayed at the surface for almost half a minute or so.
DD: Possibly, the larger the mammal, the more explosive the exhalation? Elephants have unusual lungs, explained by their snorkel-trunk, but also possibly due to long-time submergence as well.
MV: As for the (lack of) basicranial flexion in He, if the face/nose was upwards, the body must perhaps have been vertical I'd think.
DD: What would be the largest angle they could comfortably backfloat? I drew it at 90 degrees (sea otters and modern Hs can backfloat at 90 degrees comfortably), you are suggesting 180 degrees when surfacing. Would they backfloat with eyes closed and submerged, or eyes above water? Nostrils may have remained sealed at surface (philtrum-septum valve) while mouth breathing, or alternatively, mouth closed (eating)while nostrils were open above surface.
MV: I suppose they emerged with vertical body & with the nostrils first, so I don't think they spouted in a horizontal position.
DD: Likely more forward position then, perhaps 45 degrees, (sperm whales, some balleens, sirenians?, walrus?).
MV: Did they spout through the mouth (as you drew it) or the nose or both
IYO? IYO the spouting = sneezing?
MV: Our aquarboreal theory: I tend to think early hominoids (suspension in trees) must have swum regularly [DD: face always above water, laryngeal air sacs inflated], eg, to get at the trees of other islands in the Tethys, but not that they dived a lot (although it's difficult to exclude the possibility). Wading came later IMO (early hominids, ie, even after the hominid/pongid split?). Regular diving only in Homo (although, again, earlier periods of diving can't be excluded). An external nose suggests partial aq. adapations (full aquatics have no external noses), and all apes lack this feature (I'm not sure about prenatal stages).
MV: From "The aquatic ape theory: evidence and a possible scenario" Med.Hypoth.16:17-32, 1985: "Intranasal adaptations - All aquatic mammals are able to close the nostrils, and they do so under water. Most terrestrial mammals cannot close their nostrils. Humans have rudimentary compressor and dilatator naris muscles. An even better "nose-closing-system" in our ancestors could have been the erectile tissue of the inferior nasal concha with its uniquely [not present in other mammals AFAWK, eg, not in chimps] abundant and hypersensitive plexus cavernosus. In humans, a very sudden and complete nasal obstruction can be caused by sudden changes in humidity or temperature, e.g. going into the water, or even by laying down
(vasomotor rhinopathy). Moreover, humans have a short cycle of non-alternating fluctuations in nasal resistance: the erectile tissues of the conchae involuntarily swell and shrink with a rhythm of 90 sec (23). This corresponds to the diving-rhythm of the diving women of Korea and Japan (3). In shallow-diving aquatic endotherms, the diving-and-emerging cycle is usually less than 3 min. Enhydra, for example, dives for 30 to 40 sec to catch a few mussels or sea-hedgehogs, and then emerges and floats on the surface for about the same time to crack and eat them (see Stage III)." I still think it's correct, although I would now formulate it more cautiously...
MV: It's true that salt water (eg, sterilised sea water) can well be used to clear the nasal passages (not the sinuses): salt water (more than fresh or even physiologic water?) seems to have some decongestive effect on the nasal mucosa.
DD: What is cause of vasomotor rhinopathy? bacteria, virus, genetic?
MV: Hyperactive erectile tissue on inferior concha, often elicited by laying down, or by cold & wet weather (= the reason why viral rhinitis is often called "a cold" (common cold): it resembles vasomotor rhinopathy (but has more more rhinorrhea - allergic rhinits has more sneezing & itching).
MV: The inferior concha is the lower turbinal (I think "turbinal" & "turbinate" are interchangeable): scroll-like, thin, bony processes lined throughout by mucous membrane on the lateral walls & roof of the nasal cavity, which form a labyrinth of so-called turbinals or conchae (Schultz 1969:141). Haplorhini have less turbinals than Strepsirhini, and the olfactory epithelium is withdrawn to the remotest uppermost region, eg, adult hominids-pongids only have 3 conchae (inf.=maxillo-turbinal, middle=endoturb.I, sup.=endoturb.II); gibbons & monkeys usu.still have the naso-turbinal (uppermost turbinal) = rudimentary "agger nasi" in hominids-pongids; "early in the life of man there are still as many as 5 ethmo-turbinals laid down besides the maxillo-& naso-turbinals" (7!).
DD: Does/can Vasomotor Rhinopathy occur both in sea and freshwater?
MV: It occurs on land, of course, but I don't have the impression it's more frequent when I go swimming. Everybody (incl.non-VR patients) seems to have it to some extent: it has a (uniquely human?) nasal cycle of about 90 seconds (dry apers usu.confuse this with the "long" nasal "cycle" (also in other mammals) which is perhaps fifty times longer, and not in both conchae at the same time) with which both inferior conchae synchronously swell & shrink. The only reasonable explanation I can find for such a cycle is cyclic diving, but possibly not in the latest pre-terrestrial phase (otherwise it would have been more functional in us today when we dive I'd think).
DD: Does/can VR occur both in warm (blood temp.) and cold water?
MV: Most VR patients have more problems in misty weather.
DD: Does/can VR occur both in shallow and very deep water? Does/can VR occur
both in Vt. Head up & Head down, Hz. position?
MV: Most patients have more problems at night (horizontal position, but nobody sleeps with his head down). When we lay down on our right side, it's usu.the right nasal passage that is blocked, and v.v. This happens almost immediately. It gradually worsens by abuse of nasodilator drops (Nesivin etc.).
DD: Does/can VR occur both in active swimming and inactive sinking-diving?
MV: Yes, but AFAIK there are no studies on this.
DD: [Closeable nostrils/nares prevent water from entering nasal cavities, you are saying the same applies to VR. Could water enter the paranasal sinuses or any part of the nasal cavity if the erectile tissues are fully erected?
MV: No, the nose is completely blocked, as any VR patient can tell you (it's very frequent).
DD: Do newborns/infants/children/adults all have VR capability?
MV: To some extent, probably yes. About 10-15 years ago (when I read a lot about this), one of the few groups worldwide that studied the (short) nasal cycle was that of prof. Van Cauwenberghe from Univ.Gent (now rector of the university). IIRC he told me that the cycle is more prevalent in children than in adults. Since newborns are obligate nose-breaters, I guess they don't have it (and, see Schultz above ("early in life"=?), they still have more than 3 conchae!).
DD: Are there semi-aquatic animals that use VR in diving?
MV: AFAIK, it's unuquely human. Cetacea have special pump systems that immediately block the nasal passages, but you can hardly compare these to our nasal swelling tissue.
DD: Cetaeceans inhale 3,000 times more air than Hs in 1/2 the time a Hs takes. -Humans exchange 15% of the air we breathe normally (NOT PS), Ceteaceans an exchange 85-90% of their air (How? Sneeze?) -During sneeze, how much air is exchanged? [Critical question] -The diving reflex depends on max. temp. differential, PS does not. -PS depends on max. light differential, diving reflex does not. -Speculation: Cetae (esp. large deep whales) have a
baro-sensor or temperature-sensor which triggers exhale (sneeze IMO) through
blowhole, most likely the sensor is part of the ear or eye region, though possibly part of the blowhole or echolocation equipment. -PS is semi-voluntary in Hs, often can be delayed if necessary. -PS only occurs after in-dark for about a minute.
MV: Is this so, DD?
DD: No. Not absolute, but I've read 4-5 minutes (I doubt this was timed scientifically). [The synovial fluid in finger knuckle joints can "pop", then can't be popped for about 15 minutes, this was timed scientifically.] I don't think the PS was timed this way, and from my own experience, can happen more often than 1 time in 4 minutes. My guess is that if it was done
habitually as part of a diving respiratory cycle, it would be about 1.5 to 2.5 minutes. In modern Hs, it is variable. Problem: at 200 ft down, light is 5% visible in perfect clear seawater, but if they only dived to 50ft, too much light, no PS?
MV: The best moment to sneeze would have been at the exact moment of emerging.
If surfacing-sneezing ever existed, the exact moment must have been fine-tuned by different means: sunlight ("photic") would indeed be a good indicator I'd think, but also some CNS urge to sneeze at emerging (CO2, O2?), and perhaps cutaneous sensory afferents?
DD: -Sneezing can be done vert. or horiz., probably not underwater.
MV: When a mammal starts diving (eg, to collect underwater shellfish), it has to keep the water out of its airways by all means. This can be achieved, eg, by lengthening of the airways, by narrowing them, by evolving closure possibilities... (= in parallel). We see all of this in human ancestors: external nose, longer internal airway (can be seen on transection of human & chimp nasal cavity), cavernous venous sinuses over inferior conchae, splitlike nostrils, nostril closure in young children, upper lip + philtrum to close nostrils, perhaps velum to close posterior nares. I assume that when diving becomes perfected, only one of these remains necessary.
MV: Bronchial hyper-reactivity as well as bronchial sphincters are typical of
humans (asthma) & also of, eg, seals (Elaine "Aq.ape" p.89). - allergy: Some people have stronger IgE allergic reactions than others. I don't know whether humans are generally more allergic than apes?
MV: The nose was closed: at the nostrils & at the cavernous tissue on the conchae & at the velum. The mouth could be closed at the lips & the tongue, voluntarily (BTW, this is how we voluntarily can produce consonants at free will at different places (labial, dental etc., ie, the beginning of human speech): according to suction & eating underwater. During swallowing the larynx was closed by the epiglottis. I can't see any parallelism/convergence here between dolphins & us. Cetacea have ascended larynges, the opposite of Hs. Besides, the pressure upon the glottis would have been far too high. The vocal chords (very fine & mobile structures) are for phonation, not for closing the airways underwater. This was done by the tongue & the epiglottis.
Laryngospasm is a reflex also seen in terr.mammals, to protect against food, fluids, insects... falling/flying into the airways. Of course, they closed when water came in, but not or at least not in the first place because we were semi-aquatic.
MV: - There is a so-called "long" cycle, ill-defined, about 1 to 4 hours, a general fluctuation of the nasal passages, usu.alternating right & left, not typically human. (I guess it has to do with olfaction or with cleansing of the nasal passages?)
- There is a typically-human "short" cycle of ~90 seconds, in which both nasal passages at the same time narrow by swelling of the venous plexus on the inferior nasal concha. I have no doubt this has to do with diving. At the time I corresponded with one of the investigators of this cycle,
prof. Paul van Cauwenberge (now rector of the University of Ghent), who knows what he's talking about. These swelling tissues (comparable to the corpora cavernosa in the penis) are activated by lying down, by sudden cooling & by misty weather (cf. going into the water?) - the reason why "common cold" (in fact, a viral infection by rhinoviruses of the upper airways) is often thought to be caused by "cold". People who suffer a lot from this common condition have "vasomotor rhinitis" (nasal obstruction due to swelling of the veins of the lower concha, ofter made worse by abusus of nasal vasocontrictors). It's the same swelling tissue that is often stimulated in allergic people (eg, pollen allergy).
MV: When a terrestial mammal finds more & more food underwater, it has to dip or dive for it, and therefore to close its airways underwater. Every adaptation that helps to close the airways will be advantageous during these early adaptations to food collection underwater: H as compared to P have longer airways, an external nose, the nostrils underneath the nose, an
inverted U in the nasal passage, narrower airways, swelling tissues on the inferior concha, an upper lip that can seal off the nostrils, nostril-closing muscles, etc.
MV: Interesting is that we seem to have 2 diving cycles: one at the conchae of ~90", and one during SAS (sleep apena syndrome) of ~60" or so. This seems to suggest that our diving habits showed at least 2 different phases?
ice age increases aquaticness?
Wet sinuses, VR, venal pooling at depth, bronchial closure... http://tech.groups.yahoo.com/group/AAT/message/38976
http://tech.groups.yahoo.com/group/AAT/message/39630
Clicking
http://tech.groups.yahoo.com/group/AAT/message/40072
Archaic pre-heidelbergensis calvaria at Ceprano Italy
http://scienceblogs.com/afarensis/2008/11/02/sunday_need_to_read_more_from/
http://www.citeulike.org/user/EsepBib/article/1122446
Common descent @ Dive Song
http://tech.groups.yahoo.com/group/AAT/message/41529
DD: Why do we sneeze, which is a complex, whole body reaction, only to remove microscopic pollen, when simply blowing the nose is more effective and more efficient? If sneezing is to remove particles, then why do people often blow their nose AFTER sneezing? And why the runny nose AFTER sneezing, if the particles are supposedly removed already? It just does not add up to natural selection for fitness.
MV: Rhinorrhea can be caused allergic reaction, viral damage &/or anti-viral reaction (rinsing away viruses/allergens)? They overlap, but generally allergy = more sneezing, VR = more obstruction, common cold (rhinoviruses) = more rhinorrhea.
Ice Age - Aquaticness effects
=====================================================
m3d: While back floating the face/mouth would out of the water, but the ears would be in the water, would you hear a clicking/humming sound emitted above the surface of the water?
DD: Sound moves about 1500 meters per second in seawater. Sound moves much more slowly in air, at about 340 meters per second. Note that both prone clicking at depth and supine humming at surface both produce sound underwater. Humming while exhaling sends sounds out of the nostrils or both nostrils and mouth which are above the water surface, however the sound is actually produced in the larynx at the glottal folds which is submersed, like the ears, while backfloating.
This means for example the infant nursing on the mother hears the air-born sound (laryngeal-nasal humming or laryngeal-oral song), while the partner below hears primarily the water-born laryngeal vibration of the humming but perhaps not any verbal consonants. One possible reason why humans don't have SC fat covering the throat especially around the adams apple may be because it would weaken (insulate) the hum/song/speech) sound transmission.
Submerged prone clicking, due to it's open mouth (bell jar) method, would travel directly from the air entrapped oral cavity to the water, without skin or fat to obstruct or insulate the sound. Therefore the chubby cheeks did not interfere with click sound transmissions. (That had confused me earlier, when trying to click with closed mouth.)
So apparently human ancestors at seashores used these: underwater open mouth clicking, supine humming in eupnea with nursing infant, clear vision at dark depth followed by whalespout sun sneezing, sunwarmed catnaps while backfloating in apnea.
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Am J Physiol Regul Integr Comp Physiol. 2008 Nov 5.
Repetitive paired stimulation of nasotrigeminal and peripheral chemoreceptor afferents cause progressive potentiation of the diving bradycardia.
Rozloznik M, Paton JF, Dutschmann M. Neuro and Sensory Physiology, Georg-August University Goettingen, Goettingen, Germany.
The hallmarks of the mammalian diving response are protective apnea and bradycardia. These cardio-respiratory adaptations can be mimicked by stimulation the trigeminal ethmoidal nerve (EN5) and reflect oxygen conserving mechanisms during breath-hold dives. Increasing drive from peripheral chemoreceptors during sustained dives was reported to enhance the diving bradycardia. The underlying neuronal mechanisms, however, are unknown. In the present study, expression and plasticity of EN5-bradycardias after paired stimulation of the EN5 and peripheral chemoreceptors was investigated in the in situ working heart-brainstem preparation. Paired stimulations enhanced significantly the bradycardic responses compared to EN5-evoked bradycardia using sub-maximal stimulation intensity. Alternating stimulations of the EN5 followed by paired stimulation of the EN5 and chemoreceptors (10 trials, 3 min interval) caused a progressive and significant potentiation of EN5-evoked diving bradycardia. In contrast, bradycardias during paired stimulation remained unchanged during repetitive stimulation. The progressive potentiation of EN5-bradycardias was significantly enhanced after microinjection of the 5-HT3 receptor agonist (CPBG hydrochloride) into the nucleus tractus solitarii (NTS), while the 5-HT3 receptor antagonist (zacopride hydrochloride) attenuated the progressive potentiation. These results suggest an integrative function of the NTS for the multi-modal mediation of the diving response. The potentiation or 'training' of a sub-maximal diving bradycardia requires peripheral chemoreceptor drive and involves neurotransmission via 5-HT3R within the NTS. Key words: diving response, plasticity, nucleus of the solitary tract.
Electrical stimulation of the anterior ethmoidal nerve produces the diving response
Paul F. McCulloch*, Kevin M. Faber and W. Michael Panneton
Department of Anatomy and Neurobiology, Saint Louis University School of Medicine, 1402 South Grand Blvd., St. Louis, MO 63104, USA Accepted 9 March 1999.
Stimulation of the upper respiratory tract usually produces apnea, but it can also produce a vagally mediated bradycardia and a sympathetically mediated increase in peripheral vascular resistance. This cardiorespiratory response, often called the diving response, is usually initiated by nasal stimulation. The purpose of this research was to investigate the anterior ethmoidal nerve (AEN) that innervates the nasal mucosa of muskrats (Ondatra zibethicus). Electrical stimulation of the AEN (typically 50 Hz, 100 μs and 500 μA) produced immediate and sustained bradycardia and cessation of respiration similar to that of the diving response. Heart rate (HR) significantly decreased from 264±18 to 121±8 bpm, with a concurrent 4.2±0.9 s apnea, during the 5 s stimulation period. BP decreased from 97.9±4.8 to 91.2±6.4 mmHg. Using estimations from (1) cross-sectional areas of AEN trigeminal ganglion cells labeled with WGA-HRP, and (2) electron microscopic analysis of the AEN, we found that approximately 65% of the AEN is composed of unmyelinated C-fibers. In addition, 72.4% of myelinated fibers from the nerves that innervate the nasal passages were of small diameter (<6 n="1142">50 s). DMR decreased by 15%, but did not differ significantly from surface metabolic rates (MR(S)) when dive duration increased from 1 to 7 min. Overall, these data suggest that DMR is almost the same as MR(S), and that Steller sea lions incur an O(2) debt during spontaneous diving that is not repaid until the end of the dive bout. This has important consequences in differentiating between the actual and ;apparent' metabolic rate during diving, and may explain some of the differences in metabolic rates reported in pinniped species.
Respir Physiol Neurobiol. 2008 Oct 9.
Estimating the effect of lung collapse and pulmonary shunt on gas exchange during breath-hold diving: The Scholander and Kooyman legacy. Fahlman A, Hooker SK, Olszowka A, Bostrom BL, Jones DR.
Global Diving Research, Ottawa, ON, Canada K2J 5E8; Department of Zoology, The University of British Columbia, 6270 University Blvd., Vancouver, BC, Canada V6T 1Z4.
We developed a mathematical model to investigate the effect of lung compression and collapse (pulmonary shunt) on the uptake and removal of O(2), CO(2) and N(2) in blood and tissue of breath-hold diving mammals. We investigated the consequences of pressure (diving depth) and respiratory volume on pulmonary shunt and gas exchange as pressure compressed the alveoli. The model showed good agreement with previous studies of measured arterial O(2) tensions ( [Formula: see text] ) from freely diving Weddell seals and measured arterial and venous N(2) tensions from captive elephant seals compressed in a hyperbaric chamber. Pulmonary compression resulted in a rapid spike in [Formula: see text] and arterial CO(2) tension, followed by cyclical variation with a periodicity determined by Q (tot). The model showed that changes in diving lung volume are an efficient behavioural means to adjust the extent of gas exchange with depth. Differing models of lung compression and collapse depth caused major differences in blood and tissue N(2) estimates. Our integrated modelling approach contradicted predictions from simple models, and emphasised the complex nature of physiological interactions between circulation, lung compression and gas exchange. Overall, our work suggests the need for caution in interpretation of previous model results based on assumed collapse depths and all-or-nothing lung collapse models.
Cheetahs of the deep sea: deep foraging sprints in short-finned pilot whales off Tenerife (Canary Islands)
Authors: Aguilar Soto, Natacha; Johnson, Mark P.; Madsen, Peter T.; Díaz, Francisca; Domínguez, Iván; Brito, Alberto; Tyack, Peter
Source: Journal of Animal Ecology, Volume 77, Number 5, September 2008 , pp. 936-947(12) Publisher: Blackwell Publishing
Summary: Empirical testing of optimal foraging models for breath-hold divers has been difficult. Here we report data from sound and movement recording DTags placed on 23 short-finned pilot whales off Tenerife to study the foraging strategies used to catch deep-water prey. Day and night foraging dives had a maximum depth and duration of 1018 m and 21 min. Vocal behaviour during dives was consistent with biosonar-based foraging, with long series of echolocation clicks interspersed with buzzes. Similar buzzes have been associated with prey capture attempts in other echolocating species.
Foraging dives seemed to adapt to circadian rhythms. Deep dives during the day were deeper, but contained fewer buzzes (median 1), than night-time deep dives (median 5 buzzes). In most deep (540-1019 m) daytime dives with buzzes, a downward directed sprint reaching up to 9 m s−1 occurred just prior to a buzz and coincided with the deepest point in the dive, suggestive of a chase after escaping prey.
A large percentage (10-36%) of the drag-related locomotion cost of these dives (15 min long) is spent in sprinting (19-79 s). This energetic foraging tactic focused on a single or few prey items has not been observed previously in deep-diving mammals but resembles the high-risk/high-gain strategy of some terrestrial hunters such as cheetahs. Deep sprints contrast with the expectation that deep-diving mammals will swim at moderate speeds optimized to reduce oxygen consumption and maximize foraging time at depth. Pilot whales may have developed this tactic to target a deep-water niche formed by large/calorific/fast moving prey such as giant squid.
Heart rate and blood pressure time courses during prolonged dry apnoea in breath-hold divers
Authors: Perini, Renza1; Tironi, Adelaide2; Gheza, Alberto2; Butti, Ferdinando2; Moia, Christian3; Ferretti, Guido2
Source: European Journal of Applied Physiology, Volume 104, Number 1, September 2008 , pp. 1-7(7) Publisher: Springer
To define the dynamics of cardiovascular adjustments to apnoea, beat-to-beat heart rate (HR) and blood pressure and arterial oxygen saturation (SaO2) were recorded during prolonged breath-holding in air in 20 divers. Apnoea had a mean duration of 210 ± 70 s. In all subjects, HR attained a value 14 beats min−1 lower than control within the initial 30 s (phase I). HR did not change for the following 2-2.5 min (phase II). Then, nine subjects interrupted the apnoea (group A), whereas 11 subjects (group B) could prolong the breath-holding for about 100 s, during which HR continuously decreased (phase III). In both groups, mean blood pressure was 8 mmHg above control at the end of phase I; it then further increased by additional 12 mmHg at the end of the apnoea. In both groups, SaO2 did not change in the initial 100-140 s of apnoea; then, it decreased to 95% at the end of phase II. In group B, SaO2 further diminished to 84% at the end of phase III. A typical pattern of cardiovascular readjustments was identified during dry apnoea. This pattern was not compatible with a role for baroreflexes in phase I and phase II. Further readjustment in group B may imply a role for both baroreflexes and chemoreflexes. Hypothesis has been made that the end of phase II corresponds to physiological breakpoint.
Undersea Hyperb Med. 2008 May-Jun;35(3):163-7.
Barotraumatic orbital emphysema of rhinogenic origin in a breath-hold diver: a case report. Bolognini A, Delehaye E, Cau M, Cosso L. Sardinian Institute of Hyperbaric and Subaquatic Medicine, Sassari, Italy.
Orbital emphysema is a well-recognized complication of fractures involving the orbit. Commonly, it occurs when high pressure develops in nasal cavity as during nose blowing, coughing or Valsalva's maneuver and usually occurs in the subcutaneous tissues. We report the case of a young breath-hold diver who developed spontaneous, non compressive orbital emphysema during underwater fishing, with a maximal depth of 25-30 meters in the Sardinian sea. He was otherwise healthy, without previous cranio-facial trauma and nasosinusal diseases or surgery were not present in the history. When he was referred to our attention the patient presented right eyelid ptosis but diplopia and vision impairment were absent. Computer tomography scans showed subcutaneous air in the right upper eyelid and around the eyeball, particularly near the orbit's roof but optic nerve area, intraconal, was free of air. A dehiscence in lamina papyracea was evident. In our opinion, this has been the point of air entry into the orbit. A supportive therapy was advised and two weeks later the emphysema was recovered completely and the subject was symptoms free. The literature has been revised and to our knowledge no previous cases of barotraumatic orbital emphysema, in a breath-hold diver, are referred.
J Comp Physiol [B]. 2008 Nov 5.
Terrestrial apnoeas and the development of cardiac control in Australian fur seal (Arctocephalus pusillus doriferus) pups.
Deacon NL, Arnould JP. School of Life and Environmental Sciences, Deakin University, 221 Burwood Highway, Burwood, VIC, 3125, Australia.
The development of cardiac control in association with terrestrial respiration patterns was examined throughout the period of maternal dependence in Australian fur seal pups. Resting eupnoic heart rate and respiration rate were significantly correlated (r (2) = 0.49) and both decreased with age (P < href="http://news.bbc.co.uk/2/hi/science/nature/7358868.stm">http://news.bbc.co.uk/2/hi/science/nature/7358868.stm
A humid corridor across the Sahara for the migration of early modern humans
out of Africa 120,000 years ago AH Osborne cs 2008 PNAS 105:16444-7
It is widely accepted that modern humans originated in sub-Saharan Africa 150-200 thousand years ago (ka), but their route of dispersal across the currently hyperarid Sahara remains controversial. Given that the first modern humans north of the Sahara are found in the Levant 120-90 ka, northward dispersal likely occurred during a humid episode in the Sahara within Marine Isotope Stage (MIS) 5e (130-117 ka). The obvious dispersal route, the Nile, may be ruled out by notable differences between archaeological finds in the Nile Valley and the Levant at the critical time. Further west, space-born radar images reveal networks of now-buried fossil river channels that extend across the desert to the Mediterranean coast, which represent alternative dispersal corridors. These corridors would explain scattered findings at desert oases of Middle Stone Age Aterian lithic industries with bifacial and tanged points that can be linked with industries further to the east and as far north as the Mediterranean coast. Here we present geochemical data that demonstrate that water in these fossil systems derived from the south during wet episodes in general, and penetrated all of the way to the Mediterranean during MIS 5e in particular. This proves the existence of an uninterrupted freshwater corridor across a currently hyperarid region of the Sahara at a key time for early modern human migrations to the north and out of Africa. http://news.bbc.co.uk/2/hi/science/nature/7668250.stm
Previous data show there was increased rainfall across the southern part of the Sahara between 130,000 and 170,000 years ago; in a gap between Ice Ages known as the last interglacial period.
Although it is unclear which routes they took to get there, Homo sapiens had reached the Levant by around 100,000 years ago, where their remains are known from Es Skhul and Qafzeh in Israel. However, this appears to have been an early, failed foray outside Africa by modern humans (??). By 75,000 years ago, Neanderthals had replaced our species in the region. Then, about 45,000 years ago, modern humans reoccupied the area. Genetic evidence suggests that populations living outside Africa today are the descendents of a migration which originated in the east of the continent between 60-70,000 years ago.
Scientists have identified a major climate drought crisis that struck Africa about 70,000 years ago and which may have changed the course of human history. http://news.bbc.co.uk/2/hi/science/nature/4505516.stmThe evidence comes from sediments drilled up from the beds of Lake Malawi and Tanganyika in East Africa, and from Lake Bosumtwi in Ghana. It shows equatorial Africa experienced a prolonged period of drought.
Quaternary fossil fish from the Kibish Formation, Omo Valley, EthiopiaJ Trapani 2008 JHE 55:521-530
The late Quaternary Kibish Fm preserves environments reflecting a history of fluctuations in the level of nearby Lake Turkana over the past 200 ky. The Kibish Fm has yielded a diverse mammalian fauna (+ birds & crocodiles), stone tools, & the oldest anatomically modern Hs. Fish, the most common vertebrate fossils in this unit, are reported in this study. Catfish (esp.clariids & Synodontis) & Nile perch Lates niloticus predominate, but the gymnarchid Gymnarchus, a cyprinid (Barbus), tigerfish (Hydrocynus) , pufferfish (Tetraodon) & other catfish are also present. In total, 9 teleost genera are found in the Kibish Fm, representing a subset of
the 37 genera that constitute the modern Omo-Turkana ichthyo-fauna. Several taxa present in the modern fauna, incl.Polypterus & members of Cichlidae, are not found in the Kibish deposits. Most spms are preserved as disarticulated or broken skeletal elements, but some preservation of articulated elements (eg, sets of vertebrae, crania with lower jaws or cleithra) also occurs. Many of the catfish and Nile perch spms are larger than the largest reported from the modern river or lake. Faunas of Kibish Members I & III closely resemble one another; the fauna from Member IV contains only the 3 most common taxa (Clarias, Synodontis, Lates), though
this may result from insufficient sampling. Barbed bone points have been collected from the upper part of the fm, indicating a long association (200ka? 40ka?) between the human inhabitants & the fish fauna of the Omo Valley.
Stewart suggests that the hominid fishers would not have needed elaborate harpoons, fishhooks or other fishing paraphernalia : hyenas, leopards, baboons & other mammals occasionally catch fish without the benefit of technology. And traditional African fishers today sometimes
scoop fish up by hand. Several common African freshwater fish are easy to catch, esp.at certain
times of year. The best catching times would have been when fish congregated to spawn in shallow water during the rainy season, and when they were stranded in pools during the dry season : fat reserves in some fish increase towards the end of the dry season, just before spawning, which makes them esp. nutritious. Only at rel. recent African sites dating up to 50 ka have fish bones been considered as evidence that fish were an important seasonal food. Fish remains have been recorded from several early hominid sites, among them E. & W.Turkana in Kenya, Senge in Zaire, Olduvai Gorge in Tanzania, eg, at Olduvai Gorge, >4000 fragments of fish bone (catfish or Tilapia) were recovered from deposits ass.x H.habilis or the later H.erectus. The hominids lived close to a shallow, saline, alkaline lake.
M174
http://dienekes.blogspot.com/2008/10/60000-year-old-y-chromosome-haplogroup.htmlhttp://www.nyu.edu/gsas/dept/anthro/disotell/vitae.html paper on mol. clock
Divergence dates
- Homo-Pan 6.0 Ma,
- Pongo-hominines 14.0 Ma,
- hominoid/cercopithe coid 23.0 Ma.
Because a uniform mol.clock does not fit the catarrhine mtDNA data, we
estimated divergence dates using a penalized likelihood & a Bayesian method
(both take into account the effects of rate differences on lineages),
phylogenetic tree structure & multiple calibration points.
The penalized likelihood method applied to the coding regions of the mtDNA
genome yielded the following divergence date estimates:
- cercopithecine- colobine 16.2 Ma (14.4-17.9),
- colobin-presbytin, 10.9 Ma (9.6-12.3),
- cercopithecin- papionin, 11.6 Ma (10.3-12.9),
- Macaca-Papio, 9.8 Ma (8.6-10.9).
Within the hominoids :
- hylobatid-hominid 16.8 Ma (15.0-18.5),
- Gorilla-Homo+ Pan 8.1 Ma (7.1-9.0),
- Po. py. pygmaeus-Po.py. abelii 4.1 Ma (3.5-4.7),
- Pan troglodytes- paniscus 2.4 Ma (2.0-2.7).
===========================================================
technology
(from plucking, nut cracking, oyster shelling, nest weaving)
from simple to complex craft
stone simple (hand axe)
pebble + chop outside -> sharp core + chips
stone/bone complex
punching maul/awl, hafted axe/adze
wood simple (dugout canoe)
hollow log + chop inside -> dugout + chips
wood complex
dugout + adze -> thin side planks, lighter boat portage
fiber simple
strips + bundle/braid/weave -> nest, mattress
fiber complex
basket, basket boat, tri axial weave, knotted net
pelt simple
fur/skin/rawhide + deflesh/defat -> fur cape
pelt complex
cape + punch/sew -> leather clothes, skin boats
Stone - detach to create, attach hafting
Wood - detach to create, attach planking
Fiber - attach to create
Pelt - detach to create, attach sewing
Friday, October 3, 2008
Marine Science & Protection
http://www.infozine.com/news/stories/op/storiesView/sid/31028/
Ocean less livable for marine mamals?
http://news.nationalgeographic.com/news/2008/10/081002-noisy-oceans.html?source=rss
Red tide biotoxins from harm to medicine
http://www.newswise.com/articles/view/544930/?sc=rssn
Finally, an online game "saving the coral reef from an oil tanker spill", I really like the background music.
http://www.kongregate.com/games/Trickysheep/kaleidoscope-reef
Ocean less livable for marine mamals?
http://news.nationalgeographic.com/news/2008/10/081002-noisy-oceans.html?source=rss
Red tide biotoxins from harm to medicine
http://www.newswise.com/articles/view/544930/?sc=rssn
Finally, an online game "saving the coral reef from an oil tanker spill", I really like the background music.
http://www.kongregate.com/games/Trickysheep/kaleidoscope-reef
Tuesday, September 23, 2008
Hominins ate seafood
<...and sometimes seafood ate hominins...>
http://www.slagoon.com/
http://www.nytimes.com/2008/09/23/science/23obfish.html
Neanderthal exploitation of marine mammals in Gibraltar
C. B. Stringer, J. C. Finlayson et al, Communicated by Erik Trinkaus, Washington University, St. Louis, MO, June 16, 2008 (received for review April 22, 2008)
Abstract
Two coastal sites in Gibraltar, Vanguard and Gorham's Caves, located at Governor's Beach on the eastern side of the Rock, are especially relevant to the study of Neanderthals. Vanguard Cave provides evidence of marine food supply (mollusks, seal, dolphin, and fish). Further evidence of marine mammal remains was also found in the occupation levels at Gorham's Cave associated with Upper Paleolithic and Mousterian technologies [Finlayson C, et al. (2006) Nature 443:850–853]. The stratigraphic sequence of Gibraltar sites allows us to compare behaviors and subsistence strategies of Neanderthals during the Middle Paleolithic observed at Vanguard and Gorham's Cave sites. This evidence suggests that such use of marine resources was not a rare behavior and represents focused visits to the coast and estuaries.
Neanderthals Took Hunt for Food to the Sea
By HENRY FOUNTAIN Published: September 22, 2008
The Neanderthals were seafood lovers, new findings suggest.
Paleontologists digging in sediments at two large caves on a Gibraltar beach have found clear evidence that more than 30,000 years ago, Neanderthals ate mussels and other mollusks, fish and even marine mammals like seals and dolphins. And it was not that this bounty just fell into their lap: there are other signs that they actively hunted some of their seafood, just as they did with land animals.
Yolanda Fernández-Jalvo of the National Museum of Natural Sciences in Madrid, Christopher B. Stringer of the Natural History Museum in London and colleagues identified the remains of meals, including bones from monk seals and common and bottlenose dolphins, in Gorham’s and Vanguard caves on the eastern side of the rock. The findings are reported in The Proceedings of the National Academy of Sciences.
Some of the bones showed damage from stone tools, probably from the Neanderthals’ removing the meat from them. At Vanguard cave, the researchers found a hearth; evidence suggested it was used not for cooking but for preparing the seal and dolphin carcasses (for one thing, heating them would make the bones easier to break and the marrow easier to remove).
The location of the remains at Vanguard cave indicates that it had at least three periods of use by the Neanderthals. And many of the bones were from immature mammals, raising the possibility that the Neanderthals hunted during breeding season, when seals came on land for long periods to breed. Taken together, the evidence points to the Neanderthals’ making deliberate visits to the coast in search of delicacies from the deep.
http://tech.groups.yahoo.com/group/AAT/message/48495
http://www.slagoon.com/
http://www.nytimes.com/2008/09/23/science/23obfish.html
Neanderthal exploitation of marine mammals in Gibraltar
C. B. Stringer, J. C. Finlayson et al, Communicated by Erik Trinkaus, Washington University, St. Louis, MO, June 16, 2008 (received for review April 22, 2008)
Abstract
Two coastal sites in Gibraltar, Vanguard and Gorham's Caves, located at Governor's Beach on the eastern side of the Rock, are especially relevant to the study of Neanderthals. Vanguard Cave provides evidence of marine food supply (mollusks, seal, dolphin, and fish). Further evidence of marine mammal remains was also found in the occupation levels at Gorham's Cave associated with Upper Paleolithic and Mousterian technologies [Finlayson C, et al. (2006) Nature 443:850–853]. The stratigraphic sequence of Gibraltar sites allows us to compare behaviors and subsistence strategies of Neanderthals during the Middle Paleolithic observed at Vanguard and Gorham's Cave sites. This evidence suggests that such use of marine resources was not a rare behavior and represents focused visits to the coast and estuaries.
Neanderthals Took Hunt for Food to the Sea
By HENRY FOUNTAIN Published: September 22, 2008
The Neanderthals were seafood lovers, new findings suggest.
Paleontologists digging in sediments at two large caves on a Gibraltar beach have found clear evidence that more than 30,000 years ago, Neanderthals ate mussels and other mollusks, fish and even marine mammals like seals and dolphins. And it was not that this bounty just fell into their lap: there are other signs that they actively hunted some of their seafood, just as they did with land animals.
Yolanda Fernández-Jalvo of the National Museum of Natural Sciences in Madrid, Christopher B. Stringer of the Natural History Museum in London and colleagues identified the remains of meals, including bones from monk seals and common and bottlenose dolphins, in Gorham’s and Vanguard caves on the eastern side of the rock. The findings are reported in The Proceedings of the National Academy of Sciences.
Some of the bones showed damage from stone tools, probably from the Neanderthals’ removing the meat from them. At Vanguard cave, the researchers found a hearth; evidence suggested it was used not for cooking but for preparing the seal and dolphin carcasses (for one thing, heating them would make the bones easier to break and the marrow easier to remove).
The location of the remains at Vanguard cave indicates that it had at least three periods of use by the Neanderthals. And many of the bones were from immature mammals, raising the possibility that the Neanderthals hunted during breeding season, when seals came on land for long periods to breed. Taken together, the evidence points to the Neanderthals’ making deliberate visits to the coast in search of delicacies from the deep.
http://tech.groups.yahoo.com/group/AAT/message/48495
Thursday, July 31, 2008
Diving-Surfacing: Parallel Convergence
The blue whale's nose resembles the human nose and sea otter nose during backfloating.
Backfloating & Swimming: Infant 15 months old: Breathe on back, Swim on stomach
http://www.btaquatics.org/PPSwim.htm
The Aquaphotic Respiratory Cycle (ARC)
Explanation:
The Aquaphotic Respiratory Cycle (ARC) contains two components, relying upon the trigeminal cranial nerve:
1) submergence - Mammalian Divers Reflex (MDR) (stifled inhale)
2) emergence - Photic Sneeze (PS) (explosive exhale)
The MDR (from air surface to ~2m+ water depth) occurs when the face is
suddenly pressured, chilled and darkened which results in a inhale
reflex BUT since the face is submerged underwater, the inhaling reflex
is stifled and converted into O2 conservation or Mammalian Divers Reflex.
Human Physiology, Klinke, Silbernagel et al., 2006,
MDR: trigeminal cranial afferent nerve (V) relays the information that the
nasal and mouth cavities are submerged, which triggers the autonomus
nervous system to
* bradicardia, meaning a reduction of heart rate to about 4/5 of
normal rate
* blood "shift"(?) to the thorax to support the lung when under
pressure to keep it from collapsing (which would be bad for numerous
reasons)
* vasoconstriction, first in the limbs to protect vital organs,
and later of everything except the heart and the brain, which creates
a heart-brain circuit
The PS (from ~2m+ water depth to air surface) occurs when the face is
suddenly well lit after dark adaptation (accomodation for improved vision), (pressure and thermal changes
increase neural stimulus) -> fast forced CO2 exhale reflex and
"instant" oxygenation of tissues.
http://forums.deeperblue.com/freediving-science/79552-diving-surfacing-efficiently.html
DDeden [AAT, Deeper Blue, The ARC blog]
http://www.sciencedaily.com/videos/2006/0105-ear_popper.htm
The Ear-Popper is a handheld, battery-powered device that delivers a
constant, controlled stream of air pressure and flow into the nasal
cavity, diverting air up the Eustachian tube when the patient
swallows. This "pops" the ear so the fluid can drain, unblocking the
ear and restoring hearing.
http://en.wikipedia.org/wiki/Trigeminal_nerve
http://en.wikipedia.org/wiki/Facial_nerve
http://en.wikipedia.org/wiki/Cranial_nerves
http://scienceblogs.com/afarensis/2008/08/17/this_bloke_is_chuffed_a_book_r/
Chapter five, appropriately called "Getting Ahead", begins with Shubin
studying cranial nerves several days before an anatomy test. Most
cranial are easy because they have only one function and attach to one
muscle or organ. Four, however, are a bit more difficult to trace.
Shubin focuses on two of the four - the trigeminal and the facial.
Each breaks up into a number of smaller branches that take a complex
path through the head. The trigeminal nerves controls some of the
muscles we use for chewing, innervate teeth, control some muscles in
the inner ear, and is responsible for facial sensation. The facial
nerve controls the muscles used in making facial expressions and like
the trigeminal, it also controls some muscles in the inner ear. The
question is why? As Shubin puts it:
Nothing about them seems to make any sense. For example, both the
trigeminal and the facial nerves send tiny branches to muscles inside
our ears. Why do two different nerves, which innervate entirely
different parts of the face and jaw, send branches to ear muscles that
lie adjacent to one another? Even more confusing, the trigeminal and
facial almost crisscross as they send branches to our face and jaw. Why? To answer that we need to look at the developing embryo. Part of the answer lies in the four arches that for roughly 3-4 weeks after
conception. The first arch tissues, ultimately, form the upper and
lower jaws, the malleus and incus, and all the muscles that supply
them. The second arch forms the stapes, the hyoid and the muscles that
control facial expression. The trigeminal comes from the first arch,
while the facial nerve comes from the second. But there is more. In
sharks, the first arch forms the jaws, which are enervated by the
trigeminal. The second arch, in sharks, forms a cartilage rod that
eventually breaks up to form to bones that support the jaws. The first
bone is the equivalent to the hyoid in humans and supports the lower
jaw. The second bone, which supports the upper jaw is equivalent to
the stapes in humans. oing a step further, if we look at Amphioxus we
can see a notochord. Humans have one too, but ours breaks up early in
embryology and, according to Shubin, becime part of the intervertebral
disks. Like humans, Amphioxus also has arches. In this case, the
arches form cartilage that support the gill slits. Going back in time,
say 500 million years, we can see the notochord preserved in some of
the earliest worm fossils.
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