Interesting news confirms earlier speculations
link
Public release date: 20-Apr-2007
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Contact: Anna-Lynn Wegener
wegener@embl.de
49-622-138-7452
European Molecular Biology Laboratory
Researchers discover that the centralised nervous system of
vertebrates is much older than expected
The rise of the central nervous system (CNS) in animal evolution has
puzzled scientists for centuries. Vertebrates, insects and worms
evolved from the same ancestor, but their CNSs are different and were
thought to have evolved only after their lineages had split during
evolution. Researchers from the European Molecular Biology Laboratory
(EMBL) in Heidelberg now reveal that the vertebrate nervous system is
probably much older than expected. The study, which is published in
the current issue of Cell, suggests that the last common ancestor of
vertebrates, insects and worms already had a centralised nervous
system resembling that of vertebrates today.
Many animals have evolved complex nervous systems throughout the
course of evolution, but their architectures can differ substantially
between species. ...all these species descend from a common ancestor
called Urbilateria. If this ancestor already possessed a nervous
system, what it might have looked like and how it gave rise to the
diversity of nervous systems seen in animals today is what Detlev
Arendt and his group study at EMBL. To do so, they investigate the
nervous system of a marine annelid worm called Platynereis dumerilii.
"Platynereis can be considered a living fossil," says Arendt, "it
still lives in the same environment as the last common ancestors used
to and has preserved many ancestral features, including a prototype
invertebrate CNS. Comparing the molecular fingerpint of Platynereis
nerve cells with what is known about vertebrates revealed surprising
similarities.
"Our findings were overwhelming," says Alexandru Denes, who carried
out the research in Arendt's lab. "The molecular anatomy of the
developing CNS turned out to be virtually the same in vertebrates and
Platynereis. Corresponding regions give rise to neuron types with
similar molecular fingerprints and these neurons also go on to form
the same neural structures in annelid worm and vertebrate."...
The findings provide strong evidence for a theory that was first put
forward by zoologist Anton Dohrn in 1875. It states that vertebrate
and annelid CNS are of common descent and vertebrates have turned
themselves upside down throughout the course of evolution.
"This explains perfectly why we find the same centralised CNS on the
backside of vertebrates and the bellyside of Platynereis," Arendt
says. "How the inversion occurred and how other invertebrates have
modified the ancestral CNS throughout evolution are the next exciting
questions for evolutionary biologists."
http://chancenecessity.blogspot.com/2009/02/geoffroys-lobster-and-animal-common.html
-
update
To continue, with slight clarification, if interested:
See Neil Shubins slideshow, especially page 6 slide 5, to compare Hox gene positions in human and fruit fly.
http://tiktaalik.uchicago.edu/book-tools.html
My earlier explanation of primitive pentadactylity (5 digits) didn't well cover the duplication of reptile/mammal rear limbs from the forelimb carriage, this duplication is actually the same as the duplication of (beetle) 4 wings / 4 jaw mouthparts from the primitive frontal digits.
Saturday, April 21, 2007
Friday, April 20, 2007
faces from afar?
Ape facial expressions foster group harmony [via MV @ AAT]
link
Facial identification in semi-vertical float-wading anthropoids would be significant.
[I'll have to reread this and edit it, it's just a few thoughts about the significance of facial identification resulting from semi-vertical wading]
The Suaq Swamp orangutans are social, not isolated. Borneo orangs may have suffered a population bottleneck (typhus-like?) which resulted an asocial reproductive system. Borneo orangs are said to have more violent sex, possibly the bottleneck reduced the Borneo male education system, so loner/"rapist" type behavior became dominant, as opposed to chimp/bonobo group, gorilla harem, gibbon partnership and suaq orang "village". A significant clue might be this: Borneo orangs don't attempt to eat seeds from neesia fruit, but Suaq swamp orangs do using stick tools held in their lips. These neesia seeds are very high in fats, very beneficial to eaters. I'd say the Borneo orangs lost this important knowledge (sex and food habits) due to a dramatic effect, ie a bottleneck. I think they have been separate for 1/2 million years.
During Ice Age lowering of sea levels, perhaps only the Sumatran (Suaq) orangs connected to mainland South East Asia, leaving the Borneo orangs isolated.
The facial expression = group cohesion model fits well with Estuarboreal Anthropoids, if the LCA grouped in tidal water and evolved primitive laryngeal air sacs as a sinus or pocket in the soft tissue in the throat, which later diversified into the variety of air sacs seen today (see 4 common types). The oldest known monkeys had paranasal sinuses (Egypt), some have since lost them (savanna baboons), PNS combined with lar. air sacs would have kept the face up above the water but the rest of the body immersed and used to vocalize.
This Anthropoid LCA seems to have split into monkeys and apes, with the monkeys having variable tail lengths and air sacs and PNS, while the apes had a more limited base. Imaginary example: Anthropoids started from species of tarsiers (now extinct) which rafted from Madagascar to Afar, they were already partly estuarboreal, but had been niche-defined by competing lemurs and tarsiers which did not exist at Afar. Afar probably lacked thick rainforest but had monsoonal forest with seabirds nesting on rocks, fruit bats and mangroves without land predators (perhaps birds), and water may have been too salty for much crocs. At least a million years passed, before sea levels dropped, those which expanded outward along mangrove coast tropical rainforests became the miocene apes and continued to semi-vertically float-wade, while monkey ancestors expanded into monsoonal inland forests that developed in Arabia, apes expanded to both Eurasia and Africa during global wet period, then monkeys expanded into the drier Arabian forests (and circle north west into Egypt and Africa, as well as travel through Asia) when climate changed, miocene apes reduced.
Meanwhile, afar was still producing anthropoids (perhaps the barbary macaques were the last monkeys there) some which would develop into Hominoids remaining at the same area but during a sea rise the macaques and hylobatids expanded east along the coasts. Pongids split east later along coasts, while LCA HPG expanded into Africa in many waves as the region was uplifted and the island became a part-time peninsula. allowing some 2way traffic. G moved further inland, HP stayed coastal.
Most likely the OWM split from the ape LCA, moving upstream to more terrestrial habitat, while the NWM was coastal and somehow got to SA. The ape LCA
NWM may have floated across the Atlantic to Brazil, if they possessed some brackish-water processing, closeable air sacs and ate fish, krill and seaweed and could sleep in branches without nesting, the chances of survival would improve. If OTOH the LCA anthropoid was a strict freshwater primate, how could they survive such a trip? Antarctica?
link
Facial identification in semi-vertical float-wading anthropoids would be significant.
[I'll have to reread this and edit it, it's just a few thoughts about the significance of facial identification resulting from semi-vertical wading]
The Suaq Swamp orangutans are social, not isolated. Borneo orangs may have suffered a population bottleneck (typhus-like?) which resulted an asocial reproductive system. Borneo orangs are said to have more violent sex, possibly the bottleneck reduced the Borneo male education system, so loner/"rapist" type behavior became dominant, as opposed to chimp/bonobo group, gorilla harem, gibbon partnership and suaq orang "village". A significant clue might be this: Borneo orangs don't attempt to eat seeds from neesia fruit, but Suaq swamp orangs do using stick tools held in their lips. These neesia seeds are very high in fats, very beneficial to eaters. I'd say the Borneo orangs lost this important knowledge (sex and food habits) due to a dramatic effect, ie a bottleneck. I think they have been separate for 1/2 million years.
During Ice Age lowering of sea levels, perhaps only the Sumatran (Suaq) orangs connected to mainland South East Asia, leaving the Borneo orangs isolated.
The facial expression = group cohesion model fits well with Estuarboreal Anthropoids, if the LCA grouped in tidal water and evolved primitive laryngeal air sacs as a sinus or pocket in the soft tissue in the throat, which later diversified into the variety of air sacs seen today (see 4 common types). The oldest known monkeys had paranasal sinuses (Egypt), some have since lost them (savanna baboons), PNS combined with lar. air sacs would have kept the face up above the water but the rest of the body immersed and used to vocalize.
This Anthropoid LCA seems to have split into monkeys and apes, with the monkeys having variable tail lengths and air sacs and PNS, while the apes had a more limited base. Imaginary example: Anthropoids started from species of tarsiers (now extinct) which rafted from Madagascar to Afar, they were already partly estuarboreal, but had been niche-defined by competing lemurs and tarsiers which did not exist at Afar. Afar probably lacked thick rainforest but had monsoonal forest with seabirds nesting on rocks, fruit bats and mangroves without land predators (perhaps birds), and water may have been too salty for much crocs. At least a million years passed, before sea levels dropped, those which expanded outward along mangrove coast tropical rainforests became the miocene apes and continued to semi-vertically float-wade, while monkey ancestors expanded into monsoonal inland forests that developed in Arabia, apes expanded to both Eurasia and Africa during global wet period, then monkeys expanded into the drier Arabian forests (and circle north west into Egypt and Africa, as well as travel through Asia) when climate changed, miocene apes reduced.
Meanwhile, afar was still producing anthropoids (perhaps the barbary macaques were the last monkeys there) some which would develop into Hominoids remaining at the same area but during a sea rise the macaques and hylobatids expanded east along the coasts. Pongids split east later along coasts, while LCA HPG expanded into Africa in many waves as the region was uplifted and the island became a part-time peninsula. allowing some 2way traffic. G moved further inland, HP stayed coastal.
Most likely the OWM split from the ape LCA, moving upstream to more terrestrial habitat, while the NWM was coastal and somehow got to SA. The ape LCA
NWM may have floated across the Atlantic to Brazil, if they possessed some brackish-water processing, closeable air sacs and ate fish, krill and seaweed and could sleep in branches without nesting, the chances of survival would improve. If OTOH the LCA anthropoid was a strict freshwater primate, how could they survive such a trip? Antarctica?
Wednesday, April 18, 2007
Freshwater at the seashore
Conjecture: Humans require both salt and freshwater to maintain health. Ancestral divers at the seashores had abundant salt, but where did they get their freshwater every day? Did they walk over to the nearest river and drink it there? Well, perhaps they did, but it was risky, since large predators would be there waiting for thirsty prey to come by.
Coconuts provide a source of water, and during rainy periods, puddles and upturned shells would capture rainwater and freshwater springs would be available. Another source of water was the metabolic freshwater produced by the body from eating foods in addition to the free water inside fish.
Another likely source is rivers continuously pouring out their freshwater into the sea. The water further down-current (past the river mouth) is far more fresh than normal seawater, being variably brackish (depending on tide height and position, in some areas about the same salinity as blood plasma) so potentially it was sustainably drinkable without resulting in electrolyte imbalance. Too much salt and too little salt are both bad, and same with too much/little water. See this article on marathons, too much freshwater + not enough supplemental salt is dangerous:
http://scienceblogs.com/bushwells/2007/01/marathon_runners_and_na_na_na.php
The body needs optimal O2 & CO2, but also needs the optimal amount of Na & Cl, I assume as much when swimming and diving as when walking or jogging along the beach especially in sunny warm tropical conditions. It has been suggested that a diver should be hydrated preperatory to a dive, it makes sense a diver should have the right balance of electrolytes as well, for better cellular and myo/hemo/neuro/cyto-globin operation, and this would affect hypercapnea and hypoxia endurance capabilities while diving.
I'm talking here about ancient divers optimizing their dive time and performance while dive-foraging on a daily basis (not emergency situations), replenishing their water balance without entering inland rivers where the tigers, lions, crocs awaited them and other thirsty prey. (Later they figured out how to make dug-out canoes with embers and stone hand-axes and were able to penetrate the rivers far inland along gallery forests in relative safety, presumably with push-pole spears etc.).
By swimming (perhaps on a boogieboard of driftwood) offshore in clear blue seawater, and swimming into the freshwater outflow for a slightly brackish drink, beyond the normal croc zone, I'd think the only large predator would be the bull shark, which will enter large rivers easily but AFAIK doesn't target small freshwater stream outflows. I assume they used a sort of knife-blade-spatula to pry molluscs and crustaceans and perhaps spear slow groundfish and as a weapon against sharks, this tool would take the place of large canine teeth. (Chimps have been seen using sharpened sticks to spear prey in tree hollows, that's not too different from using sharp sticks to spear groundfish or sharks.)
I should note though, that some seas are very high in chemicals which cause other problems even when diluted to a brackish level, eg. Dead Sea is high in Magnesium which causes diarrhea. Of course in modern days, river outflow water would have to be checked for pollution hazards.
[Note: For more info, see also my website at THE-ARC.wikispaces]
DDeden
Director, Naturalist, Author & Songwriter
The Humboldt Eureka - Aquamarine Research Center
Coconuts provide a source of water, and during rainy periods, puddles and upturned shells would capture rainwater and freshwater springs would be available. Another source of water was the metabolic freshwater produced by the body from eating foods in addition to the free water inside fish.
Another likely source is rivers continuously pouring out their freshwater into the sea. The water further down-current (past the river mouth) is far more fresh than normal seawater, being variably brackish (depending on tide height and position, in some areas about the same salinity as blood plasma) so potentially it was sustainably drinkable without resulting in electrolyte imbalance. Too much salt and too little salt are both bad, and same with too much/little water. See this article on marathons, too much freshwater + not enough supplemental salt is dangerous:
http://scienceblogs.com/bushwells/2007/01/marathon_runners_and_na_na_na.php
The body needs optimal O2 & CO2, but also needs the optimal amount of Na & Cl, I assume as much when swimming and diving as when walking or jogging along the beach especially in sunny warm tropical conditions. It has been suggested that a diver should be hydrated preperatory to a dive, it makes sense a diver should have the right balance of electrolytes as well, for better cellular and myo/hemo/neuro/cyto-globin operation, and this would affect hypercapnea and hypoxia endurance capabilities while diving.
I'm talking here about ancient divers optimizing their dive time and performance while dive-foraging on a daily basis (not emergency situations), replenishing their water balance without entering inland rivers where the tigers, lions, crocs awaited them and other thirsty prey. (Later they figured out how to make dug-out canoes with embers and stone hand-axes and were able to penetrate the rivers far inland along gallery forests in relative safety, presumably with push-pole spears etc.).
By swimming (perhaps on a boogieboard of driftwood) offshore in clear blue seawater, and swimming into the freshwater outflow for a slightly brackish drink, beyond the normal croc zone, I'd think the only large predator would be the bull shark, which will enter large rivers easily but AFAIK doesn't target small freshwater stream outflows. I assume they used a sort of knife-blade-spatula to pry molluscs and crustaceans and perhaps spear slow groundfish and as a weapon against sharks, this tool would take the place of large canine teeth. (Chimps have been seen using sharpened sticks to spear prey in tree hollows, that's not too different from using sharp sticks to spear groundfish or sharks.)
I should note though, that some seas are very high in chemicals which cause other problems even when diluted to a brackish level, eg. Dead Sea is high in Magnesium which causes diarrhea. Of course in modern days, river outflow water would have to be checked for pollution hazards.
[Note: For more info, see also my website at THE-ARC.wikispaces]
DDeden
Director, Naturalist, Author & Songwriter
The Humboldt Eureka - Aquamarine Research Center
Thursday, April 12, 2007
Rest In Peace
Loic Leferme, explorer, free-diver
Kurt Vonnegut Jr., author, wrote on marine iguana
Knut Schmidt-Nielson, comparative physiologist
Daryl Habel, paleoanthropologist
All influenced me
All recently passed away
My condolences to the families and friends
David Deden
Kurt Vonnegut Jr., author, wrote on marine iguana
Knut Schmidt-Nielson, comparative physiologist
Daryl Habel, paleoanthropologist
All influenced me
All recently passed away
My condolences to the families and friends
David Deden
__________________
"Dive well and come up for more"
The-Arc-of-a-Diver: the-arc.wikispaces.com
"Dive well and come up for more"
The-Arc-of-a-Diver: the-arc.wikispaces.com
Deep Science: Dive Song (contd.)
Hypothesis testing: Flooded nasal cavity-ARC correlation
[Caution: Do not attempt without ENT physiology background]
While standing vertical or while prone, not much success due to non-voluntary leakage, perhaps due to lack of practice. While supine, with head lowermost, allowed H2O saline (table salt mixed in tap water) into nasal cavity to fill. No discomfort, but not much effect either. Unknown if sinuses were filled, assume they were, unknown if middle ear s were filled, attempted to fill middle ears via holding nostrils and pressurizing with tongue, some swishing but not certain if successful, now hearing is slightly tinnitus-like in right ear but hearing seems aerobic. Now waiting to see if any additional drainage occurs, none noticed. Difficult to determine for sure whether cavities are air or water filled. Valving is not well understood or implemented at this time. Post effects not noticeable, same as previous to test, except moisture laden. Difficult to determine during test the various dive positions effects, vertical vs horizontal, due to gravity and non-buoyant conditions. During descent, no significant difficulties expected, during horizontal at depth, no difficulties expected, during ascent possibly problematic due to possible leakage. Now left nare partly clogged, right nare open.
From surface, hypothetically submerge face and allow water into nostrils while head is lowest, until nasal cavity seems filled but not overfilled.
During test, alphabet (except M, N) pronounced, clicks and various sounds made, no humming possible.
Yet to be found: middle ear condition while submerged, regarding hearing and equalization.
Left ear Eustachian tubes easily manipulated, aerated via pinching nose and pressurising (followed by automatic burp & reduction of pressure with brief slight pain), but right ear ET not voluntarily adjustable at this time possible, right ET is water filled but unlikely. Why right ET only slightly adjustable, yet left nare is partly clogged? Right ET is currently and recent-historically about 1/3 as inflatable when pinching nares and pressurising, possibly due to earwax accumulation near eardrum of right ear(?), or some other cause (possibly scars from childhood earache history, although never noticed previous to 5 years ago, also possibly related to wisdom teeth removal but this is doubted). No previous history of adult ear problems.
Still uncertain: middle ears and sinuses water filled or not. Now both ET are adjustable, although right ET less so.
Require better determination of flooded middle ears and sinuses.
After test, sniffed black pepper, no sneeze even after trying a few times vigorously, went outside to bright sun and sneezed once due to combined sunlight and pepper.
Just noticed: present burping caused slight pain in left middle ear due to pressure differential.
By adjusting jaw a bit, left ET pressure is alleviated.
1/2 hour later slight nasal leakage, probably from water in sinus traps.
3 hours later: very very slight ear warming and pressure, stuffy feeling in ears, nose normal but slightly more sensitive to smell and tactile.
4+ hours later: normal condition
Assumption: Water was too fresh, not salty enough, caused stuffy feeling.
Testing continues.
DDeden
[Caution: Do not attempt without ENT physiology background]
While standing vertical or while prone, not much success due to non-voluntary leakage, perhaps due to lack of practice. While supine, with head lowermost, allowed H2O saline (table salt mixed in tap water) into nasal cavity to fill. No discomfort, but not much effect either. Unknown if sinuses were filled, assume they were, unknown if middle ear s were filled, attempted to fill middle ears via holding nostrils and pressurizing with tongue, some swishing but not certain if successful, now hearing is slightly tinnitus-like in right ear but hearing seems aerobic. Now waiting to see if any additional drainage occurs, none noticed. Difficult to determine for sure whether cavities are air or water filled. Valving is not well understood or implemented at this time. Post effects not noticeable, same as previous to test, except moisture laden. Difficult to determine during test the various dive positions effects, vertical vs horizontal, due to gravity and non-buoyant conditions. During descent, no significant difficulties expected, during horizontal at depth, no difficulties expected, during ascent possibly problematic due to possible leakage. Now left nare partly clogged, right nare open.
From surface, hypothetically submerge face and allow water into nostrils while head is lowest, until nasal cavity seems filled but not overfilled.
During test, alphabet (except M, N) pronounced, clicks and various sounds made, no humming possible.
Yet to be found: middle ear condition while submerged, regarding hearing and equalization.
Left ear Eustachian tubes easily manipulated, aerated via pinching nose and pressurising (followed by automatic burp & reduction of pressure with brief slight pain), but right ear ET not voluntarily adjustable at this time possible, right ET is water filled but unlikely. Why right ET only slightly adjustable, yet left nare is partly clogged? Right ET is currently and recent-historically about 1/3 as inflatable when pinching nares and pressurising, possibly due to earwax accumulation near eardrum of right ear(?), or some other cause (possibly scars from childhood earache history, although never noticed previous to 5 years ago, also possibly related to wisdom teeth removal but this is doubted). No previous history of adult ear problems.
Still uncertain: middle ears and sinuses water filled or not. Now both ET are adjustable, although right ET less so.
Require better determination of flooded middle ears and sinuses.
After test, sniffed black pepper, no sneeze even after trying a few times vigorously, went outside to bright sun and sneezed once due to combined sunlight and pepper.
Just noticed: present burping caused slight pain in left middle ear due to pressure differential.
By adjusting jaw a bit, left ET pressure is alleviated.
1/2 hour later slight nasal leakage, probably from water in sinus traps.
3 hours later: very very slight ear warming and pressure, stuffy feeling in ears, nose normal but slightly more sensitive to smell and tactile.
4+ hours later: normal condition
Assumption: Water was too fresh, not salty enough, caused stuffy feeling.
Testing continues.
DDeden
Wednesday, April 11, 2007
Deep Science: Dive Song
Here is where science meets music & diving in human prehistory and today
[Caution: Do not attempt tests without ENT physiology background]
Eureka!! Another discovery at THE-ARC!
Harmonic intervals in sound & structure
The ossified skeletal ribcage and/or vertebral column may
have originally evolved partly as a sound receiver, where
calcium (critical for hearing in inner ears) accumulated
in the cartilage for better hearing. Note the parabolic
rib cage and aerial antennae-like vertebral column, this
Pre-Homo-sapiens condition is primitive and continued in
early Homo sapiens via very thick dense bones and
occiput. Consider the very dense bones of the sirenians,
which were mistakenly thought to be deaf, but are now
known to have good hearing.
Obviously the skeleton is primarily structural now, but
that may have been a result of initial sound improvement.
Now from Synergeo group:
The oral clicking is something I've researched, it most
likely goes back at least 20,000 years, and IMO much
further back in time. The Khoisan peoples (including many
different tribes Hottentots, Hazde, !Kung, ...) use
clicks as consonants, and likely consonants are derived
from clicks IMO. Khoisan has 4 tones and 4 clicks, while
Chinese has 4 tones but the 4 clicks have derived into
consonants, other languages have largely lost both the
tones and clicks, replacing them with various sounds.
Dive-Song hypothesis suggests that while in seawater,
our ancestors communicated via humming (the person at
the surface) and clicking (the person at depth seeking
lobsters, clams, sea urchins). Parallels in clicking
include dolphins, sperm whales, walruses, seals, and
croaker fish and snapping shrimp, while parallels in
humming include blue whale (whalesong), walruses,
manatees. I don't know if sea otters vocalize under
water, but they do at the surface.
This is part of the reason why I was interested in the
12 & 31 links, to see if harmony and the Ico/VE
splitting related to bones. Sound travels far far better
through water than through air, IF the ears are adapted
to water-bone conduction (seawater in nose and middle
ears, but soft palate valve closed).
Here's a neat thought: Have you noticed that the spinal
vertebrae and the ribs extend out quite similarly to
some kinds of antennae, like TV aerial antenae? What is
the difference between a parabolic dish antenae, a single
straight antennae and a branched antenae on a roof?
-O Dish antenae
______ Pole antenae
->>> Aerial antenae
<<<<<= Rooftop aerial ../|\.. If sound is transmitted along the ribs to the nerves and if vertebrae transmit sound to spinal column via electrochemical paths and set to the brain... Now think of Bucky Fuller's geodesic domes, "radomes" which housed radar receivers in the arctic, with a fiberglass shell exterior and a metal antennae inside the dome, the fiberglass allowed transmission through the walls. So does dolphin skin and fat and so does human fat and skin, while bone deflects sound waves. The only thing that stops sonar in the body (I think) is air bubbles (in the bone and soft tissue). Ancient divers allowed water into the middle ear when diving via the nostrils, while keeping the soft palate closed, this equalized the ears & sinuses while reducing buoyancy during dive, and using the surface water means that the sinuses and middle ears had warmth even during a deep cold dive. Whales instead have middle ears with blood vessels which fill with blood, which again allows sound transmission. If one subscribes to the idea that the sphere is sort of the base in nature, and that all other shapes derive from it, and therefore relate to it both regarding physical matter and forms of energy (sound waves, light waves), then the 31 and 12 "coincidences" fit patterns. The 31 and 12 positions aren't speculation, they are fact. But interpreting them as correlative is speculative. I followed 2 rules: 1) the basal (simplest) form in nature is the sphere 2) the basal (simplest) structure in nature is the tetrahedron. With 2) being a subset of this: The (4 sided) tetrahedron, (8 sided) octahedron and (20 sided) icosahedron are the only structural forms in the universe. All other structural forms are multiples of or are derived from these primary structures. [paraphrased from Bucky Fuller's Synergetics] Beyond that, humans are not spherical, but note the roundedness of the tips of the fingers, the tip of the nose, etc. What about hair? Primitively, hair is round per cross section. Among Central Africans, far inland from seashore diving, frizzy/curly hair developed via natural selection as a way to prevent blood sucking body lice (which can spread typhus) from attaching their eggs to frizzy hair. So, hair is dead and like skin sells eventually are disposed of, so hair can grow long (due to strong protein strands). Feathers tend to maintain roundness because they have blood flow. Sound is spherical, expanding from a source point, like light. Human embryogenesis is initially spherical and divides the egg according to symmetrical rules 1/2, 1/4, ... Being a naturalist, I like to see how nature operates. http://home.usit.net/~rybo6/rybo/id7.html
This link ties together some things of note: primes, nucleus magic numbers, equilateral sphere division into 31 (structural 5 fold icosahedral) and 25 non-structural 4 fold cuboctahedral), sine waves on 4 levels (remniscent of a snake's sinusoidal propulsion), etc.
The 31 spinal pairs, with an anterior spherical skullcase, in the human species, does indeed seem significant. The sphere is the simplest form (sea turtle egg (sphere) is more primitive than chicken egg (ovoid) because it wasn't selected against like the chicken egg (which had gone through a cliff-nesting stage where spherical eggs
were less likely to survive).
The human skull (sphere-like) is more primitive than most other animals, it is less prognathic or out-of round, in part due to food aquisition methods which don't require special features (saber teeth). The spine and vertebrae are derived from the skull, they once were the propulsion mechanism, as the tail of the zooflagellate is.
An animal that moves much in water (eel) typically has a rounded cross section and lengthened axis. However, an animal that moves little or not at all tends to be more sphere like (sponge). The method of food gathering and digestion would affect greatly the form of the body.
math
http://home.usit.net/~rybo6/rybo/id6.html
nucleus sphericity and magic numbers
http://the-arc-ddeden.blogspot.com/2007/04/spatial-geometry-nuclear-physics.html
Skull & spine
http://f1.grp.yahoofs.com/v1/sDsZRk-IcwiqXmRei0o6Xo40RfiA78LwgFe_etxM-LGovghW5d5lcFu817-
lfM_yMEbJzOmMBDCaWia-HZfjt8grXsD-XqOVVUQE/A%20Rybonic%20Folder/Spinal31.PNG
It would seem that the coalescence at 12 and 31 might be insignificant coincidence, but if musical sound structure, spatial form structure, and human embryogenetic primary skeletal structure are all viewed simply as energy cycles in the continuum of mass to/from energy, then it is not surprising.
The difficulty with attributing universal significance to any feature of the European harmonic system is that it is contingent upon the nature of the dominant instruments of the musical culture. In western "art" music, the bowed string and blown wind instruments (including the human voice) dominate. Because their vibrations are forced (energy is continually provided) these produce sounds with harmonic partials,
as a consequence of which harmonic intervals (those with frequency ratios that can be expressed in small integers) sound acoustically smooth. In musical cultures where the dominant instruments are tuned percussion (notably Javanese and Balinese gamelan) other intervals sound smoother and different scales (e.g. the pelog and slendro scales of the gamelan, which sound very unfamiliar to Western ears) make use of them.
For further discussion see:
http://www.mooremusic.org.uk/schenk/index.htm
Much of this essay is concerned with musical analysis. However, the acoustic arguments outlined above are given more fully in Chapter 4 and in the books by Benade and Sethares (see References).
Ken Moore
Thanks Ken, interesting. Forced air and vocalizing sends sound forward to the listener via convection I guess (more so in dry, cool air?), while gamelans, bronze bells and gongs and nasal song/humming are less directive and more diffused (more effective in humid, warm air conduction?).
Tropical Asians use their hands in dancing much more than their feet, and speak with many ng- sounds; Northerly Westerners attend to steps and body movements while dancing, with hands for grasping partners, and rarely initiate words with ng- sounds.
Seems like climate plays a significant part in these various styles.
DD
[Caution: Do not attempt tests without ENT physiology background]
Eureka!! Another discovery at THE-ARC!
Harmonic intervals in sound & structure
The ossified skeletal ribcage and/or vertebral column may
have originally evolved partly as a sound receiver, where
calcium (critical for hearing in inner ears) accumulated
in the cartilage for better hearing. Note the parabolic
rib cage and aerial antennae-like vertebral column, this
Pre-Homo-sapiens condition is primitive and continued in
early Homo sapiens via very thick dense bones and
occiput. Consider the very dense bones of the sirenians,
which were mistakenly thought to be deaf, but are now
known to have good hearing.
Obviously the skeleton is primarily structural now, but
that may have been a result of initial sound improvement.
Now from Synergeo group:
The oral clicking is something I've researched, it most
likely goes back at least 20,000 years, and IMO much
further back in time. The Khoisan peoples (including many
different tribes Hottentots, Hazde, !Kung, ...) use
clicks as consonants, and likely consonants are derived
from clicks IMO. Khoisan has 4 tones and 4 clicks, while
Chinese has 4 tones but the 4 clicks have derived into
consonants, other languages have largely lost both the
tones and clicks, replacing them with various sounds.
Dive-Song hypothesis suggests that while in seawater,
our ancestors communicated via humming (the person at
the surface) and clicking (the person at depth seeking
lobsters, clams, sea urchins). Parallels in clicking
include dolphins, sperm whales, walruses, seals, and
croaker fish and snapping shrimp, while parallels in
humming include blue whale (whalesong), walruses,
manatees. I don't know if sea otters vocalize under
water, but they do at the surface.
This is part of the reason why I was interested in the
12 & 31 links, to see if harmony and the Ico/VE
splitting related to bones. Sound travels far far better
through water than through air, IF the ears are adapted
to water-bone conduction (seawater in nose and middle
ears, but soft palate valve closed).
Here's a neat thought: Have you noticed that the spinal
vertebrae and the ribs extend out quite similarly to
some kinds of antennae, like TV aerial antenae? What is
the difference between a parabolic dish antenae, a single
straight antennae and a branched antenae on a roof?
-O Dish antenae
______ Pole antenae
->>> Aerial antenae
<<<<<= Rooftop aerial ../|\.. If sound is transmitted along the ribs to the nerves and if vertebrae transmit sound to spinal column via electrochemical paths and set to the brain... Now think of Bucky Fuller's geodesic domes, "radomes" which housed radar receivers in the arctic, with a fiberglass shell exterior and a metal antennae inside the dome, the fiberglass allowed transmission through the walls. So does dolphin skin and fat and so does human fat and skin, while bone deflects sound waves. The only thing that stops sonar in the body (I think) is air bubbles (in the bone and soft tissue). Ancient divers allowed water into the middle ear when diving via the nostrils, while keeping the soft palate closed, this equalized the ears & sinuses while reducing buoyancy during dive, and using the surface water means that the sinuses and middle ears had warmth even during a deep cold dive. Whales instead have middle ears with blood vessels which fill with blood, which again allows sound transmission. If one subscribes to the idea that the sphere is sort of the base in nature, and that all other shapes derive from it, and therefore relate to it both regarding physical matter and forms of energy (sound waves, light waves), then the 31 and 12 "coincidences" fit patterns. The 31 and 12 positions aren't speculation, they are fact. But interpreting them as correlative is speculative. I followed 2 rules: 1) the basal (simplest) form in nature is the sphere 2) the basal (simplest) structure in nature is the tetrahedron. With 2) being a subset of this: The (4 sided) tetrahedron, (8 sided) octahedron and (20 sided) icosahedron are the only structural forms in the universe. All other structural forms are multiples of or are derived from these primary structures. [paraphrased from Bucky Fuller's Synergetics] Beyond that, humans are not spherical, but note the roundedness of the tips of the fingers, the tip of the nose, etc. What about hair? Primitively, hair is round per cross section. Among Central Africans, far inland from seashore diving, frizzy/curly hair developed via natural selection as a way to prevent blood sucking body lice (which can spread typhus) from attaching their eggs to frizzy hair. So, hair is dead and like skin sells eventually are disposed of, so hair can grow long (due to strong protein strands). Feathers tend to maintain roundness because they have blood flow. Sound is spherical, expanding from a source point, like light. Human embryogenesis is initially spherical and divides the egg according to symmetrical rules 1/2, 1/4, ... Being a naturalist, I like to see how nature operates. http://home.usit.net/~rybo6/rybo/id7.html
This link ties together some things of note: primes, nucleus magic numbers, equilateral sphere division into 31 (structural 5 fold icosahedral) and 25 non-structural 4 fold cuboctahedral), sine waves on 4 levels (remniscent of a snake's sinusoidal propulsion), etc.
The 31 spinal pairs, with an anterior spherical skullcase, in the human species, does indeed seem significant. The sphere is the simplest form (sea turtle egg (sphere) is more primitive than chicken egg (ovoid) because it wasn't selected against like the chicken egg (which had gone through a cliff-nesting stage where spherical eggs
were less likely to survive).
The human skull (sphere-like) is more primitive than most other animals, it is less prognathic or out-of round, in part due to food aquisition methods which don't require special features (saber teeth). The spine and vertebrae are derived from the skull, they once were the propulsion mechanism, as the tail of the zooflagellate is.
An animal that moves much in water (eel) typically has a rounded cross section and lengthened axis. However, an animal that moves little or not at all tends to be more sphere like (sponge). The method of food gathering and digestion would affect greatly the form of the body.
math
http://home.usit.net/~rybo6/rybo/id6.html
nucleus sphericity and magic numbers
http://the-arc-ddeden.blogspot.com/2007/04/spatial-geometry-nuclear-physics.html
Skull & spine
http://f1.grp.yahoofs.com/v1/sDsZRk-IcwiqXmRei0o6Xo40RfiA78LwgFe_etxM-LGovghW5d5lcFu817-
lfM_yMEbJzOmMBDCaWia-HZfjt8grXsD-XqOVVUQE/A%20Rybonic%20Folder/Spinal31.PNG
The difficulty with attributing universal significance to any feature of the European harmonic system is that it is contingent upon the nature of the dominant instruments of the musical culture. In western "art" music, the bowed string and blown wind instruments (including the human voice) dominate. Because their vibrations are forced (energy is continually provided) these produce sounds with harmonic partials,
as a consequence of which harmonic intervals (those with frequency ratios that can be expressed in small integers) sound acoustically smooth. In musical cultures where the dominant instruments are tuned percussion (notably Javanese and Balinese gamelan) other intervals sound smoother and different scales (e.g. the pelog and slendro scales of the gamelan, which sound very unfamiliar to Western ears) make use of them.
For further discussion see:
http://www.mooremusic.org.uk/schenk/index.htm
Much of this essay is concerned with musical analysis. However, the acoustic arguments outlined above are given more fully in Chapter 4 and in the books by Benade and Sethares (see References).
Ken Moore
Thanks Ken, interesting. Forced air and vocalizing sends sound forward to the listener via convection I guess (more so in dry, cool air?), while gamelans, bronze bells and gongs and nasal song/humming are less directive and more diffused (more effective in humid, warm air conduction?).
Tropical Asians use their hands in dancing much more than their feet, and speak with many ng- sounds; Northerly Westerners attend to steps and body movements while dancing, with hands for grasping partners, and rarely initiate words with ng- sounds.
Seems like climate plays a significant part in these various styles.
DD
Thursday, April 5, 2007
Spatial Geometry & Nuclear Physics
Nucleus geometry: sequence of "magic numbers" modelled as nested polyhedrons as filled nucleonic shells.
http://www.rwgrayprojects.com/synergetics/s09/figs/f9503a.html
Question: Is this accurate as drawn, or is a spherical version more correct?
Nature likes spheres. The black lines describe closest links (bonds) between points, points are the proton and neutron centers. So ignoring the actual black lines, and instead see each point as center of a bubble, then does it become spheroid?
The sphere in nature:
least surface area, maximal surface tension in equilibrium of non-crystaline sub-units.
In a body full of non-crystaline sub-units, for each sub-unit (eg. nucleons) to have the maximum number of bonds (contact points), the body must be spherical, any other form will result in fewer contact points in sum.
If the sub-units have weak bonds, the sphere allows the most secure body, simply due to the higher number of contact points per sub-unit. A sphere of weakly bonded sub-units may be stronger than a non-sphere with strongly bonded sub-units.
So regarding the nucleus, if double magic, the body is spherical with maximized contact points.
" ", if not magic, the body will compact towards a sphere-like condition in order to maximize bonds.
The exception occurs when the nucleus is double magic plus one extra nucleon, in which the extra nucleon has the least number of contact points, and so partially protrudes from the sphere. For every additional nucleon added, the sum of contact points is greater, so it tends toward greater sphericity.
This proves that nucleus is never cigar-shaped (except when the sum of nucleons = 2) or disk shaped (except when the sum of nucleons = 3), but instead, the nucleus is always spheroidal except during fusion or fission.
The neutrons act as buffers between the protons allowing this tight spherical fit. If the number of neutrons is less than protons, then the protons can't seat properly into the sphere shell, and will stay on the surface (reducing sphericity of the body) reducing the body density and thus the perceived gravity.
I figure...
DDeden
http://www.rwgrayprojects.com/synergetics/s09/figs/f9503a.html
Question: Is this accurate as drawn, or is a spherical version more correct?
Nature likes spheres. The black lines describe closest links (bonds) between points, points are the proton and neutron centers. So ignoring the actual black lines, and instead see each point as center of a bubble, then does it become spheroid?
The sphere in nature:
least surface area, maximal surface tension in equilibrium of non-crystaline sub-units.
In a body full of non-crystaline sub-units, for each sub-unit (eg. nucleons) to have the maximum number of bonds (contact points), the body must be spherical, any other form will result in fewer contact points in sum.
If the sub-units have weak bonds, the sphere allows the most secure body, simply due to the higher number of contact points per sub-unit. A sphere of weakly bonded sub-units may be stronger than a non-sphere with strongly bonded sub-units.
So regarding the nucleus, if double magic, the body is spherical with maximized contact points.
" ", if not magic, the body will compact towards a sphere-like condition in order to maximize bonds.
The exception occurs when the nucleus is double magic plus one extra nucleon, in which the extra nucleon has the least number of contact points, and so partially protrudes from the sphere. For every additional nucleon added, the sum of contact points is greater, so it tends toward greater sphericity.
This proves that nucleus is never cigar-shaped (except when the sum of nucleons = 2) or disk shaped (except when the sum of nucleons = 3), but instead, the nucleus is always spheroidal except during fusion or fission.
The neutrons act as buffers between the protons allowing this tight spherical fit. If the number of neutrons is less than protons, then the protons can't seat properly into the sphere shell, and will stay on the surface (reducing sphericity of the body) reducing the body density and thus the perceived gravity.
I figure...
DDeden
Tuesday, April 3, 2007
Estuarboreal & Aquarid ancestors
DM: I did [look at the Dive Song brief]. I conclude that you got the idea that human hearing has something to do with water, so you made up an elaborate scenario to explain that.
DD: Nope. I just connected the facts in the most parsimonious manner. And that my friend is Science.
DM: "Don't you read anything about chemistry, .."
DM: "Most atomic nuclei are not spheres; they occupy a wide range from cigar-shaped to disk-shaped."
DM: "it was in a Scientific American special volume that I read long ago."
DD: 1) Yes. 2) False. 3) False. One must study and understand the primacy of the spherical shape in nature before one can speak intelligibly about egg shapes, planets, nuclear fission-fusion, meiosis-mitosis, gravity-density, diffusion-radiation, conduction-convection, erosion-deposition, estrus-menstrual cycles, etc. Else it is just blowing hot air. I just connected the facts in the most parsimonious manner.
DM: It's not the most parsimonious possibility -- the whole diving stuff is not needed to explain the features you mentioned. It is an unnecessary ad hoc assumption. One must study and understand the primacy of the spherical shape in nature before one can speak intelligibly about [...]
DM: First, one must find out whether there is, in a meaningful way, such a thing as "the primacy of the spherical shape in nature". You assume a priori that there's a common underlying reason for all spheres, even if this necessitates introducing an ad hoc assumption. What if one sphere has nothing to do with another?
DD: Odd statement, sphere's share common sphericity, that is not nothing.
DM: And no, spheres have zero to do with meiosis, mitosis, gravity, density, or menstruation. If you have evidence to the contrary, please tell me.
DD: "spherical shape of most nuclei" as I referenced earlier, do you dispute that? Even simple nuclei tend toward sphericity, although they don't resemble perfect spheres due to having only a small quantity of neutrons and protons. Eg. a nucleus of 2 P and 2 N might appear tetrahedral, but are the most spherically possible shape when Nucleons = 4.
To avoid repeating, here's an online text helpful in comprehending the properties of common sphericity in nature, by the inventor of the geodesic dome.
http://www.rwgrayprojects.com/synergetics/synergetics.html
The tiny inner ear cells in humans are hairs (hair cells), derived from the anterior sensory hairs of the lateral line in fish. Yes, it has something to do with water, sound energy frequencies (vibrations) provide information about the environment, likely these hairs had once been external vibrissae for the crustacean-fish last common ancestor.
However, I was speaking of the middle ears, the little bones and eustachian tubes to the nasal cavity. A human non-scuba diver can submerge and allow seawater into the nasal cavity and middle ears (in order to avoid gas-equalization problems at depth), while the soft palate separates the nasal cavity from the oral cavity.
Notably sound is then magnified (increased sound conduction via bones and dissonance is reduced) at depth, as compared to having air filled middle ears, since there is electrolytic liquid in the inner ears, middle ears, and external ears. Thus humans retain a weak form of sonar capability, though far inferior to that of the specialized fish chasing dolphins.
Dive-Song is simply the brief description of the causative agent for many "special" traits of humans. White eyes (enlarged sclerae), monogamy, reduced size dimorphism compared to apes, singing, humming, clicking, music, epicanthal eyelids, primitive pinnae, unusual breathing adaptations, photic sneezing, eating raw shellfish, gift-giving-trade, sustained vocal communication, facial gestures, much reduced laryngeal air sacs compared to similar sized apes, etc. etc.
Speculative zoology? Yes, but strongly correlative biology and ecology and anthropology (when not dismissed by savanna-centered theorists). Does Dive-Song answer all the questions? No just a few of the hardest.
Savanna woodlands were occupied by humans much much later, after development of dug-out boats and tools allowed safe passage inland, previous to that trees and cliffs provided the only refuge from large predators, producing the arboreal apes. Tropical rainforests inland were obviously not where humans diverged from other apes.
DDeden
DD: I used those as modern examples (reindeer, grey whales, figs) as parallels with past events of evolutionary significance, since I'm not familiar with specific pre-pleistocene mammals and plants.
MD: Here we have the problem. Why do you talk about things that you know full well you don't understand? Learn about them first, and then come back -- before then you won't know which parts of today's biosphere are parallels to past conditions and which are not.
DD: Point taken, I doubt I have much time to dig so deeply and thoroughly. However, life today does not differ very much from life 20 or 200 million years ago, if one understands natural selection, which I do, and one has good data on climate-environmental changes which I don't.
DDeden
(My "I see" comment refers to my underappreciation of the diversity of snake tooth shapes.)
Please substantiate your claim that "ppt" means "part per trillion".
Don't you read anything about chemistry, including reports of pollution? Google for "parts per trillion", and you'll see... percent, permil, ppm, ppb, ppt, ppq. I have seen "ppt" used for "parts per thousand", but that's a rare mistake.
DD: I've found nothing to substantiate your claim. Please provide a ref.
Sorry, it was in a Scientific American special volume that I read long ago. But what results did you get from googling for "double magic" nucleus? Does none of them help?
The tiny inner ear cells in humans are hairs, derived from the anterior sensory hairs of the lateral line in fish.
They are not hairs, they are cilia (and thus outgrowths of cells, not that it matters here). Cilia occur in lots of sense organs, like vertebrate eyes and the lateral line organ, so you're right that the inner ear and the lateral line organ are on some level the same, "fish" have their own inner ears. We're talking about vertebrate inner ears, not human inner ears which are in no way special.
likely these hairs had once been external vibrissae for the crustacean-fish last common ancestor.
No, that common ancestor had cilia all over its skin and used them for locomotion (in addition to having specialized cilia in certain sense organs, e.g. one kind of eye). Flatworms, nemertines and several other clades still move that way most of the time (like Paramecium).
Notably sound is then magnified (increased sound conduction via bones and dissonance is reduced) at depth, as compared to having air filled middle ears, since there is electrolytic liquid in the inner ears, middle ears, and external ears.
Fine.
Thus humans retain a weak form of sonar capability
Hearing in water is not the same as sonar, just like hearing in air is not the same as sonar -- bats have sonar, we don't.
The soft palate is common to all mammals.
Dive-Song is simply the brief description of the causative agent for many "special" traits of humans. White eyes (enlarged sclerae), monogamy, reduced size dimorphism compared to apes, singing, humming, clicking, music, epicanthal eyelids, primitive pinnae, unusual breathing adaptations, photic sneezing, eating raw shellfish, gift-giving-trade, sustained vocal communication, facial gestures, much reduced laryngeal air sacs compared to similar sized apes, etc. etc.
Fine, but it's still a just-so story. It doesn't explain anything that can't be explained otherwise. (Except maybe for the sclerae -- can you direct me to more info about those? What are epicanthal eyelids, and what do you mean by pinnae -- certainly not the external ears?) Let me try:
- We are, on average, not monogamous. We fuck around almost like bonobos.
- Reduced size dimorphism comes with reduced male-male competition, as do the shrunken canines and the absence of large laryngeal air sacs. Make love, not war... see above.
- Music including singing and humming can be explained in lots of other ways that don't necessitate regular diving. Try communication. Anything can come out of a brain as bloated as ours.
- Clicking? Do you mean click consonants?
-- These have probably developed from consonant clusters. Plenty of languages in West Africa today have coarticulated kp and/or gb, that is, you put the tongue against the velum, close the lips, and then open both closures at almost the same time. Try pronouncing that. More often than not you'll open the lips just before instead of just after the velar closure. Voilà , the bilabial click. link
-- The idea that the last common ancestor of all extant languages contained click consonants comes from the idea that the Khoisan languages are the sister-group to all the rest. Even if that is true, and even if the presence of clicks in all Khoisan languages is retained (plesiomorphic) instead of an innovation (autapomorphic), clicks can still have arisen in the MRCA of all extant languages as described above. Keep in mind that there's no evidence that the MRCA of all extant languages was the first language; most likely, it was spoken long after the first language.
- What do you mean by "unusual breathing adaptations", and how many of these have been tested in other mammals, especially other apes? It is indeed interesting that our heart rate drops when we dive -- but we don't know if the same happens to a chimp, because chimps don't dive. Maybe we could convince an orang-utan to do it; they do go quite deep into water if they need to.
- "Photic sneezing" means having to sneeze when looking into the sun, right? I don't have that, and I don't think it's widespread, so I don't think it's likely that any population of our ancestors all had it. On the other hand, how widespread is it beyond humans? Do any chimps have it?
- We are the only apes that ever get a chance to eat raw shellfish. You don't know if there's any "special trait of humans" involved here; as long as you don't, you can't hope to explain anything about it.
- Gifts are widespread among mammals and birds. Trade and communication come with a bloated brain -- and how other than vocal would you communicate? Constantly having to look at each other is a disadvantage. I'm trying to say "sustained vocal communication" doesn't need an explanation at all.
- Facial gestures are normal for Old World monkeys at the least. Nothing to explain here.
Savanna woodlands were occupied by humans much much later, after development of dug-out boats and tools allowed safe passage inland,
Then why do we find their remains long, long before any kind of boat?
previous to that trees and cliffs provided the only refuge from large predators, producing the arboreal apes.
Arboreality is the normal state for primates; it does not need to be explained. You are right that the loss of arboreality needs to be explained -- and that happened twice, because 5 % of all surviving chimps live in the savanna. Predators are not much of a concern for a group of chimps; they are famous for putting up a fight, with weapons.
Tropical rainforests inland were obviously not where humans diverged from other apes.
The oldest human remains do not come from outright rainforests, but still from wooded environments with a more or less closed canopy. The savanna came later, when the forest shrunk.
DM: I did [look at the Dive Song brief]. I conclude that you got the idea that human hearing has something to do with water, so you made up an elaborate scenario to explain that.
Nope. I just connected the facts in the most parsimonious manner. And that my friend is Science.
DDeden
> I forgot to mention: you can't eat the eggs of a mosasaur or
plesiosaur any more than those of a stagodontid or "pediomyid"
metatherian.
On the effect of the K/Pg extinction on stagodontids:
It might be wishful thinking on my side - I happen to like stagodontids - but doesn`t Eobrasilia look like a post-K/Pg (Itaboraian) survivor?
Marshal (Journal of Paleontology, Vol 58, No 1; Jan. 1984; pp. 173-177)
seems to come to the same conclusion.
DM: "Don't you read anything about chemistry, .."
DM: "Most atomic nuclei are not spheres; they occupy a wide range from cigar-shaped to disk-shaped."
DM: "it was in a Scientific American special volume that I read long ago."
DD: 1) Yes. 2) False. 3) False. One must study and understand the primacy of the spherical shape in nature before one can speak intelligibly about egg shapes, planets, nuclear fission-fusion, meiosis-mitosis, gravity-density, diffusion-radiation, conduction-convection, erosion-deposition, estrus-menstrual cycles, etc. Else it is just blowing hot air.
DDeden
Nope. I just connected the facts in the most parsimonious manner.
It's not the most parsimonious possibility -- the whole diving stuff is not needed to explain the features you mentioned. It is an unnecessary ad hoc assumption.
One must study and understand the primacy of the spherical shape in nature before one can speak intelligibly about [...]First, one must find out whether there is, in a meaningful way, such a thing as "the primacy of the spherical shape in nature". You assume a priori that there's a common underlying reason for all spheres, even if this necessitates introducing an ad hoc assumption. What if one sphere has nothing to do with another?
And no, spheres have zero to do with meiosis, mitosis, gravity, density, or menstruation. If you have evidence to the contrary, please tell me.
Congratulations! You're reaching the average thread length of Pharyngula! :-)
"spherical shape of most nuclei" as I referenced earlier, do you dispute that? Even simple nuclei tend toward sphericity, although they don't resemble perfect spheres due to having only a small quantity of neutrons and protons. Eg. a nucleus of 2 P and 2 N might appear tetrahedral, but are the most spherically possible shape when Nucleons = 4.
Anything which places ancient human ancestors 7-1ma long distances away from the shores (previous to boats) adds complexity (abundant sweating = needs abundant salt + water, freshwater not enough).
-----
85 comments (+1).
DDeden
We just had a computer crash, I think I sent a comment just now, but not sure if it posted. To avoid repeating, here's an online text helpful in comprehending the properties of common sphericity in nature, by the inventor of the geodesic dome.
http://www.rwgrayprojects.com/synergetics/synergetics.html
DDeden
DM: Hearing in water is not the same as sonar, just like hearing in air is not the same as sonar -- bats have sonar, we don't.
DD: False. Sonar uses echoes (water or air), aka blind person with cane or oral clicking. Google.
DD: Dive-Song is simply the brief description of ...
DM: Fine, but it's still a just-so story. It doesn't explain anything that can't be explained otherwise.
DD: It explains them most parsimoniously, these functions all worked together and were selected for.
DM: (Except maybe for the sclerae -- can you direct me to more info about those? What are epicanthal eyelids, and what do you mean by pinnae -- certainly not the external ears?) Let me try:
DD: Jane Goodall found 1 chimp with white sclerae, and the albino gorilla Snowflake had white sclerae, all other apes & monkeys (and nearly all mammals) do not have exposed/enlarged white sclerae. All humans do, although Central Africans have a yellowish tint. Why? It fits perfectly into a diving scenario for our ancestors. As well the epicanthic (slant) eyelids of the Khoisan, some Nubian and Middle Eastern and East Asian people, and the previous reduction and subsequent enlargement of the pinnae and poor ear muscular control compared to typical arboreal and savanna spp.
DM: We are, on average, not monogamous. We fuck around almost like bonobos.
DD: We (viewed as all age, not just young adult) are far more monogamous than any great ape.
DM: Reduced size dimorphism comes with reduced male-male competition, as do the shrunken canines and the absence of large laryngeal air sacs. Make love, not war... see above.
DD: Is this found in any typical savanna or arboreal spp.?
Savanna chimps tend to be more dimorphic (and less bipedal) than rainforest bonobos. Since you have stated human ancestors were on the savannas, how do you resolve this?
It would however be expected to occur if the male & female (with infant) dove together alternatively, changing from direct male-male competition to male/female-male/female, something which could not occur terrestrially but could occur at the shores and arboreally (see partial parallel in gibbons re. air sacs).
DM: Music including singing and humming can be explained in lots of other ways that don't necessitate regular diving. Try communication. Anything can come out of a brain as bloated as ours.
DD: What savanna/woodland mammals sing or hum? Notably, arboreal songbirds sing, ground birds don't. Presuming our ancestors were terrestrial, what indicates that they would sing and hum? Why would they alter from a loud long call to a continuous vocalizing pattern? Mice have proportionately larger brains than humans, and they sing and live on savannas, is that the only comparison?
DM: Clicking? Do you mean click consonants?
-- These have probably developed from consonant clusters.
DD: Clicks as you noted. Ancient, unknown date of origin, possibly derived from breath holding mannerisms.
DM: What do you mean by "unusual breathing adaptations", and how many of these have been tested in other mammals, especially other apes? It is indeed interesting that our heart rate drops when we dive -- but we don't know if the same happens to a chimp, because chimps don't dive. Maybe we could convince an orang-utan to do it; they do go quite deep into water if they need to.
DD: Although uncertain, I'd guess any great ape immersed would fill their laryngeal air sac with exhaled air and could not dive.
DM: "Photic sneezing" means having to sneeze when looking into the sun, right? I don't have that, and I don't think it's widespread, so I don't think it's likely that any population of our ancestors all had it. On the other hand, how widespread is it beyond humans? Do any chimps have it?
Darwin found no sun-frown and assumably no sun-sneeze when he tested a young chimp and orang from very dark to bright light conditions. Uniquely human AFAIK, but likely similar to marine iguanas which look at the sun and sneeze to remove salt brine from nasal glands (they dive and eat salty seaweed). The photic sneeze exhales old air from the body entirely at roughly the same speed as a dolphin ventilatory cycle, far faster than a normal aerobic exhale in a human.
DM: We are the only apes that ever get a chance to eat raw shellfish. You don't know if there's any "special trait of humans" involved here; as long as you don't, you can't hope to explain anything about it.
DD: Chimps eat freshwater shrimp larvae in inland non-tidal streams underneath leaves. No apes live on tidal waters, apes developed their derivations (eg. longer fingers) as they moved from the coasts inland.
DM: Gifts are widespread among mammals and birds. Trade and communication come with a bloated brain -- and how other than vocal would you communicate?
DD: Savanna animals typically use scent and visual, vocal is usually danger-related. Mammalian gift-giving not so common (exc. chimp male exchange food for sex with older females)
DM: Constantly having to look at each other is a disadvantage. I'm trying to say "sustained vocal communication" doesn't need an explanation at all.
DD: How many inland wooded savanna spp. have sustained vocal communication?
DD: Savanna woodlands were occupied by humans much much later, after development of dug-out boats and tools allowed safe passage inland,
DM: Then why do we find their remains long, long before any kind of boat?
DD: Butted hand axe/adze remnants (Eritrea reef 125,000yrs) indicate possible dug-out contsruction. Boats rot quickly, bones less so, teeth less so. There were certainly hominids inland with at least partial arboreal adaptations, but our ancestors were generally along coasts and near-shore isles.
No doubt however there was indeed some mixing, simply due to the long periods involved.
DD: previous to that trees and cliffs provided the only refuge from large predators, producing the arboreal apes.
DM: Arboreality is the normal state for primates; it does not need to be explained. You are right that the loss of arboreality needs to be explained -- and that happened twice, because 5 % of all surviving chimps live in the savanna. Predators are not much of a concern for a group of chimps; they are famous for putting up a fight, with weapons.
DD: Fight against a small leopard perhaps, no chance against a lion, dead meat. That's why savanna chimps stay near trees, and why our ancestors avoided that whole scene until they came upstream on boats.
DM: The oldest human remains do not come from outright rainforests, but still from wooded environments with a more or less closed canopy. The savanna came later, when the forest shrunk.
DD: The further away from seashores/isles, no matter what eco-type, the less likely a non-tree-sleeper would survive, until dug-outs (and fire?), due to the big cats. Human ancestors lost their tree gripping feet a long time ago, and consider the pregnant females & chubby infants, very unlike the lightning fast quadruped baboons and patas monkeys.
I considder it most likely that at different periods, our ancestors were islanded but sometimes able to travel to coastal shores, with variable results (like sea turtles and croc populations, unlike inland theropods or sauropods). They weren't absolutely island isolates.
Gosh, enough already!
DDeden
DM: Fine, but it's still a just-so story. It doesn't explain anything that can't be explained otherwise.
DD: It explains them most parsimoniously, these functions all worked together and were selected for.
DM: (Except maybe for the sclerae -- can you direct me to more info about those? What are epicanthal eyelids, and what do you mean by pinnae -- certainly not the external ears?) Let me try:
DD: Jane Goodall found 1 chimp with white sclerae, and the albino gorilla Snowflake had white sclerae, all other apes & monkeys (and nearly all mammals) do not have exposed/enlarged white sclerae. All humans do, although Central Africans have a yellowish tint. Why? It fits perfectly into a diving scenario for our ancestors. As well the epicanthic (slant) eyelids of the Khoisan, some Nubian and Middle Eastern and East Asian people, and the previous reduction and subsequent enlargement of the pinnae and poor ear muscular control compared to typical arboreal and savanna spp.
DM: We are, on average, not monogamous. ... like bonobos.
DD: We (viewed as all age, not just young adult) are far more monogamous than any great ape.
DM: Reduced size dimorphism comes with reduced male-male competition, as do the shrunken canines and the absence of large laryngeal air sacs. Make love, not war... see above.
DD: Is this found in any typical savanna or arboreal spp.?
Savanna chimps tend to be more dimorphic (and less bipedal) than rainforest bonobos. Since you have stated human ancestors were on the savannas, how do you resolve this?
DD: It would however be expected to occur if the male & female (with infant) dove together alternatively, changing from direct male-male competition to male/female-male/female, something which could not occur terrestrially but could occur at the shores and arboreally (see partial parallel in gibbons re. air sacs).
DM: Music including singing and humming can be explained in lots of other ways that don't necessitate regular diving. Try communication. Anything can come out of a brain as bloated as ours.
DD: What savanna/woodland mammals sing or hum? Notably, arboreal songbirds sing, ground birds don't. Presuming our ancestors were terrestrial, what indicates that they would sing and hum? Why would they alter from a loud long call to a continuous vocalizing pattern? Mice have proportionately larger brains than humans, and they sing and live on savannas, is that the only comparison?
DM: Clicking? Do you mean click consonants?
-- These have probably developed from consonant clusters.
DD: Clicks as you noted. Ancient, unknown date of origin, possibly derived from breath holding mannerisms.
DM: What do you mean by "unusual breathing adaptations", and how many of these have been tested in other mammals, especially other apes? It is indeed interesting that our heart rate drops when we dive -- but we don't know if the same happens to a chimp, because chimps don't dive. Maybe we could convince an orang-utan to do it; they do go quite deep into water if they need to.
DD: Although uncertain, I'd guess any great ape immersed would fill their laryngeal air sac with exhaled air and could not dive.
DM: "Photic sneezing" means having to sneeze when looking into the sun, right? I don't have that, and I don't think it's widespread, so I don't think it's likely that any population of our ancestors all had it. On the other hand, how widespread is it beyond humans? Do any chimps have it?
DD: Darwin found no sun-frown and assumably no sun-sneeze when he tested a young chimp and orang from very dark to bright light conditions. Uniquely human AFAIK, but likely similar to marine iguanas which look at the sun and sneeze to remove salt brine from nasal glands (they dive and eat salty seaweed). The photic sneeze exhales old air from the body entirely at roughly the same speed as a dolphin "spouting" ventilatory cycle, far faster than a normal aerobic exhale in a human.
DM: We are the only apes that ever get a chance to eat raw shellfish. You don't know if there's any "special trait of humans" involved here; as long as you don't, you can't hope to explain anything about it.
DD: Chimps eat freshwater shrimp larvae in inland non-tidal streams underneath leaves. No apes live on tidal waters, apes developed their derivations (eg. longer fingers) as they moved from the coasts inland.
DM: Gifts are widespread among mammals and birds. Trade and communication come with a bloated brain -- and how other than vocal would you communicate?
DD: Savanna animals typically use scent and visual, vocal is usually danger-related. Mammalian gift-giving not so common (exc. chimp male exchange food for sex with older females)
DM: Constantly having to look at each other is a disadvantage. I'm trying to say "sustained vocal communication" doesn't need an explanation at all.
DD: How many inland wooded savanna spp. have sustained vocal communication?
DD: Savanna woodlands were occupied by humans much much later, after development of dug-out boats and tools allowed safe passage inland,
DM: Then why do we find their remains long, long before any kind of boat?
DD: Butted hand axe/adze remnants (Eritrea reef 125,000yrs) indicate possible dug-out contsruction. Boats rot quickly, bones less so, teeth less so. There were certainly hominids inland with at least partial arboreal adaptations, but our ancestors were generally along coasts and near-shore isles.
No doubt however there was indeed some mixing, simply due to the long periods involved.
DD: previous to that trees and cliffs provided the only refuge from large predators, producing the arboreal apes.
DM: Arboreality is the normal state for primates; it does not need to be explained. You are right that the loss of arboreality needs to be explained -- and that happened twice, because 5 % of all surviving chimps live in the savanna. Predators are not much of a concern for a group of chimps; they are famous for putting up a fight, with weapons.
DD: Fight against a small leopard perhaps, no chance against a lion, dead meat. That's why savanna chimps stay near trees, and why our ancestors avoided that whole scene until they came upstream on boats.
DM: The oldest human remains do not come from outright rainforests, but still from wooded environments with a more or less closed canopy. The savanna came later, when the forest shrunk.
DD: The further away from seashores/isles, no matter what eco-type, the less likely a non-tree-sleeper would survive, until dug-outs (and fire?), due to the big cats. Human ancestors lost their tree gripping feet a long time ago, and consider the pregnant females & chubby infants, very unlike the lightning fast quadruped baboons and patas monkeys.
DD: I consider it most likely that at different periods, our ancestors were islanded but sometimes able to travel to coastal shores, with variable results (like sea turtles and croc populations, unlike inland theropods or sauropods). They weren't absolutely island isolates.
Posted by: DDeden | April 3, 2007 03:33 AM
Monday, April 2, 2007
Texas Coastal Lagoons: Primate refuge 42ma
[As expected per the Estuarboreal Anthropoid Hypothesis of the ARC Theory, primate fossils have been found indicating that primates lived in coastal lagoons 42 million years ago. DD]
http://news.yahoo.com/s/ap/20070402/ap_on_sc/texas_primates_1
http://news.yahoo.com/s/ap/20070402/ap_on_sc/texas_primates_1
Team: Texas study shows ancient primates
Mon Apr 2, 5:39 PM ET
BEAUMONT, Texas - A team of anthropologists said their study of South Texas fossil deposits revealed evidence including ancient teeth that shows the area was home to numerous types of primates 42 million years ago.
Lamar University Professor Jim Westgate and two colleagues announced the discovery of three new genera and four new species of primates based on their examination of material removed from Lake Casa Blanca International State Park near Laredo and the Mexican border.
Westgate said the Laredo area was a coastal lagoon during the stage of geologic history known as the Eocene Epoch, which was when primates were becoming extinct on much of the continent.
"It was kind of the last gasp for the primates in North America," said Westgate, a professor of earth and space sciences.
The researchers presented their findings last week at a conference of the American Association of Physical Anthropologists in Philadelphia.
Westgate and others are still studying the 15 tons of material excavated from the park's fossil deposits between 1983 and 1996. Researchers recovered 1,800 mammal teeth, including 50 from primates.
Dana Cope, a co-author of the study and associate professor of anthropology at College of Charleston in South Carolina, compared the teeth with other primate teeth from the same era. He said the newly discovered teeth, which measure about 4 millimeters, were not from known primates.
"This is a very important locality," Cope said. "Not much is known about Eocene mammals outside the Rocky Mountains."
Cope said the genus the researches have focused on likely had a diet of leaves and foliage and weighed about two pounds. Its closest living relative would probably be the tarsier primate that lives in the Philippines.
Westgate said one of the project's main goals was to excavate the material and protect it for study and documentation.
"We knew way back we had something important," he said. "Now we're targeting areas that needed more research."
Wednesday, March 21, 2007
Earthly hum
Earth hums: why? The earth produces a sound which is detected by seismologists (earth-quake scholars), the source?
seismo hum story: click here
Which includes these bottom abcd pics, the max humming occurs seasonally at the bottlenecks (a=Chukchi/Bering sea flushes, b=Antarctic circumpolar current flush) yet the authors say nothing of that. Why?
My guess: the tidal grinder effect caused by the lunar-solar tidal differential and associated waves at the shallow sea coasts, (the chaordic (chaotic order) point of physical state equilibrium of solid, liquid and gas), where erosion & deposition continuously result in massive aggregate particulate displacement, which is the primary causative agent of tectonic plate migration (continental drift), splitting and then recombining supercontinents over geologic time.
Now, compare that explanation with the below abstract (correct interpretation IMO), and following summary paragraph, which (IMO incorrectly) states that movement of the plate derives from viscous traction at the base of the plate.
shelves hum story: click here
Letter Nature 445, 754-756 (15 February 2007) | doi:10.1038/nature05536; Received 2 November 2006; Accepted 12 December 2006
The Earth's 'hum' is driven by ocean waves over the continental shelves
Spahr C. Webb 1. Lamont Doherty Earth Observatory, Columbia University, Palisades, New York 10964, USA
Observations show that the seismic normal modes of the Earth at frequencies near 10 mHz are excited at a nearly constant level in the absence of large earthquakes1. This background level of excitation has been called the 'hum' of the Earth2, and is equivalent to the maximum excitation from a magnitude 5.75 earthquake3. Its origin is debated, with most studies attributing the forcing to atmospheric turbulence, analogous to the forcing of solar oscillations by solar turbulence2, 4, 5, 6, 7. Some reports also predicted that turbulence might excite the planetary modes of Mars to detectable levels4. Recent observations on Earth, however, suggest that the predominant excitation source lies under the oceans8, 9, 10. Here I show that turbulence is a very weak source, and instead it is interacting ocean waves over the shallow continental shelves that drive the hum of the Earth. Ocean waves couple into seismic waves through the quadratic nonlinearity of the surface boundary condition, which couples pairs of slowly propagating ocean waves of similar frequency to a high phase velocity component at approximately double the frequency. This is the process by which ocean waves generate the well known 'microseism peak' that dominates the seismic spectrum near 140 mHz (refs 11, 12), but at hum frequencies, the mechanism differs significantly in frequency and depth dependence. A calculation of the coupling between ocean waves and seismic modes reproduces the seismic spectrum observed. Measurements of the temporal correlation between ocean wave data and seismic data9, 10 have confirmed that ocean waves, rather than atmospheric turbulence, are driving the modes of the Earth.
plate traction summary: click here
Editor's Summary 22 March 2007
The power of plate tectonics
A compilation of seismic images, geochronology and plate-motion reconstruction has been used to compare the location and chronology of a hotspot track at the base and top of the North American lithosphere. The work reveals a conspicuous misalignment between the surface and deep parts of the tracks. Misalignment increases with age along the track, and is best explained by creep in the mantle lithosphere beneath North America. The sense of shear implied by these observations indicates that motion of the plate is driven by viscous traction at the base of the plate. This is of significance for understanding the driving forces of plate tectonics.
Letter: Seismic evidence for convection-driven motion of the North American plate
David W. Eaton and Andrew Frederiksen
doi:10.1038/nature05675
seismo hum story: click here
Which includes these bottom abcd pics, the max humming occurs seasonally at the bottlenecks (a=Chukchi/Bering sea flushes, b=Antarctic circumpolar current flush) yet the authors say nothing of that. Why?
My guess: the tidal grinder effect caused by the lunar-solar tidal differential and associated waves at the shallow sea coasts, (the chaordic (chaotic order) point of physical state equilibrium of solid, liquid and gas), where erosion & deposition continuously result in massive aggregate particulate displacement, which is the primary causative agent of tectonic plate migration (continental drift), splitting and then recombining supercontinents over geologic time.
Now, compare that explanation with the below abstract (correct interpretation IMO), and following summary paragraph, which (IMO incorrectly) states that movement of the plate derives from viscous traction at the base of the plate.
shelves hum story: click here
Letter Nature 445, 754-756 (15 February 2007) | doi:10.1038/nature05536; Received 2 November 2006; Accepted 12 December 2006
The Earth's 'hum' is driven by ocean waves over the continental shelves
Spahr C. Webb 1. Lamont Doherty Earth Observatory, Columbia University, Palisades, New York 10964, USA
Observations show that the seismic normal modes of the Earth at frequencies near 10 mHz are excited at a nearly constant level in the absence of large earthquakes1. This background level of excitation has been called the 'hum' of the Earth2, and is equivalent to the maximum excitation from a magnitude 5.75 earthquake3. Its origin is debated, with most studies attributing the forcing to atmospheric turbulence, analogous to the forcing of solar oscillations by solar turbulence2, 4, 5, 6, 7. Some reports also predicted that turbulence might excite the planetary modes of Mars to detectable levels4. Recent observations on Earth, however, suggest that the predominant excitation source lies under the oceans8, 9, 10. Here I show that turbulence is a very weak source, and instead it is interacting ocean waves over the shallow continental shelves that drive the hum of the Earth. Ocean waves couple into seismic waves through the quadratic nonlinearity of the surface boundary condition, which couples pairs of slowly propagating ocean waves of similar frequency to a high phase velocity component at approximately double the frequency. This is the process by which ocean waves generate the well known 'microseism peak' that dominates the seismic spectrum near 140 mHz (refs 11, 12), but at hum frequencies, the mechanism differs significantly in frequency and depth dependence. A calculation of the coupling between ocean waves and seismic modes reproduces the seismic spectrum observed. Measurements of the temporal correlation between ocean wave data and seismic data9, 10 have confirmed that ocean waves, rather than atmospheric turbulence, are driving the modes of the Earth.
plate traction summary: click here
Editor's Summary 22 March 2007
The power of plate tectonics
A compilation of seismic images, geochronology and plate-motion reconstruction has been used to compare the location and chronology of a hotspot track at the base and top of the North American lithosphere. The work reveals a conspicuous misalignment between the surface and deep parts of the tracks. Misalignment increases with age along the track, and is best explained by creep in the mantle lithosphere beneath North America. The sense of shear implied by these observations indicates that motion of the plate is driven by viscous traction at the base of the plate. This is of significance for understanding the driving forces of plate tectonics.
Letter: Seismic evidence for convection-driven motion of the North American plate
David W. Eaton and Andrew Frederiksen
doi:10.1038/nature05675
Friday, March 16, 2007
Struck dumb
1st tetrapods breathed through their ears
http://info.uu.se/press.nsf/pm/did.our.idF2D.html
Mystery Of Mammalian Ears Solved
http://www.sciencedaily.com/releases/2007/07/070727172839.htm
A 30-year scientific debate over how specialized cells in the inner ear
amplify sound in mammals appears to have been settled more in favor of
bouncing cell bodies rather than vibrating, hair-like cilia, according to
investigators at St. Jude Children's Research Hospital.
The finding could explain why dogs, cats, humans and other mammals have such
sensitive hearing and the ability to discriminate among frequencies. The
work also highlights the importance of basic hearing research in studies
into the causes of deafness.
"Our discovery helps explain the mechanics of hearing and what might be
going wrong in some forms of deafness," said Jian Zuo, Ph.D., the paper's
senior author and associate member of the St. Jude Department of
Developmental Neurobiology. "There are a variety of causes for hearing loss,
including side effects of chemotherapy for cancer. One strength of St. Jude
is that researchers have the ability to ask some very basic questions about
how the body works, and then use those answers to solve medical problems in
the future."
The long-standing argument centers around outer hair cells, which are
rod-shaped cells that respond to sound waves. Located in the fluid-filled
part of the inner ear called the cochlea, these outer hair cells sport tufts
of hair-like cilia that project into the fluid. The presence of outer hair
cells makes mammalian hearing more than 100 times better than it would be if
the cells were absent.
As sound waves race into the inner ear at hundreds of miles per hour, their
energy--although dissipated by the cochlear fluid--generates waves in the
fluid, somewhat like the tiny waves made by a pebble thrown into a pond.
This energy causes the hair cell cilia in both mammals and non-mammals to
swing back and forth quickly in a steady rhythm.
In mammals, the rod-shaped body of the outer hair cell contracts and then
vibrates in response to the sound waves, amplifying the sound. In a previous
study, Zuo and his colleagues showed that a protein called prestin is the
motor in mammalian outer hair cells triggers this contraction. And that is
where the debate begins.
While both mammals and non-mammals have cilia on their outer hair cells,
only mammalian outer hair cells have prestin, which drives this cellular
contraction, or somatic motility. The contraction pulls the tufts of cilia
downward, which maximizes the force of their vibration. In mammals, both the
cilia and the cell itself vibrate. Thus far the question has been whether
the cilia are the main engine of sound amplification in both mammals and
non-mammals.
One group of scientists believes that somatic motility in mammalian outer
hair cells is simply a way to change the height of the cilia in the fluid to
maximize the force with which the cilia oscillate. That, in turn, would
amplify the sound. An opposing group of scientists maintains that although
the vibration of the outer hair cell body itself--somatic motility--does
maximize the vibration of the cilia, the cell body works independently of
its cilia. That is, vibration of the mammalian cell dominates the work of
amplifying sound in mammals.
"If somatic motility is the dominant force for amplifying sound in mammals,
this would mean that prestin is the reason mammals amplify sound so
efficiently," Zuo said.
In the current study, Zuo and his team conducted a complex series of studies
that showed in mammals that the role of somatic mobility driven by prestin
is not simply to modify the response of the outer hair cells' cilia to
incoming sound waves in the cochlea fluid. Instead, somatic motility itself
appears to dominate the amplification process in the mammalian cochlea,
while the cilia dominate amplification in non-mammals.
Zuo's team took advantage of a previously discovered mutated form of prestin
that does not make the outer hair cells contract in response to incoming
sound waves as normal prestin does. Instead, the mutated form of prestin
makes the cell extend itself when it vibrates.
The St. Jude researchers reasoned that if altering the position of the cilia
in the fluid changes the ability of the cilia to amplify sound, then hearing
should be affected when the mutant prestin made the cell extend itself.
Therefore, the team developed a line of genetically modified mice that
carried only mutant prestin in their outer hair cells. The researchers then
tested the animals' responses to sound.
Results of the studies showed no alteration in hearing, which suggested that
it did not matter whether the outer hair cells contracted or extended
itself, that is, raised or lowered the cilia. There was no effect on
amplification. The researchers concluded that somatic motility was not
simply a way to make cilia do their job better; rather, there is no
connection between the hair cell contractions and how the cilia do their
job. Instead, somatic motility, generated by prestin, is the key to the
superior hearing of mammals.
A report on this work appears in the advanced online issue of "Proceedings
of the National Academy of Science."
Other authors of this study include Jiangang Gao, Xudong Wu and Manish Patel
(St. Jude); Xiang Wang, Shuping Jia and David He (Creighton University,
Omaha, Neb.); Sal Aguinaga, Kristin Huynh, Keiji Matsuda, Jing Zheng,
MaryAnn Cheatham and Peter Dallos (Northwestern University, Evanston, Ill.).
[From DB or AAT? dive down past the spherical harmony section if you like]
Regarding hearing, humming and spherical/planar/scalar harmony
Semi-circular ear canals in mammals, primates
The primate semicircular canal system and locomotion
Fred Spoor, Theodore Garland Jr, Gail Krovitz, Timothy M Ryan, Mary T Silcox
& Alan Walker 2007
The semicircular canal system of vertebrates helps coordinate body
movements, including stabilization of gaze during locomotion. Quantitative
phylogenetically informed analysis of the radius of curvature of the three
semicircular canals in 91 extant and recently extinct primate species and
119 other mammalian taxa provide support for the hypothesis that canal size
varies in relation to the jerkiness of head motion during locomotion.
Primate and other mammalian species studied here that are agile and have
fast, jerky locomotion have significantly larger canals relative to body
mass than those that move more cautiously.
From the discussion:
... The strong relationship between SCC.size & locomotor agility is clearly
evident in a variety of primate groups. The leaping tarsiers & galagos have
large canals relative to their body size, whereas the slow quadrupedal
lorises, although of similar body size, lie on the lower end of the
distribution with relatively small canals. At larger body masses, this
relationship also holds. The acrobatic brachiating gibbons have rel.large
canals for their body size, compared with the great apes. The sloth lemurs
& koala lemurs have small canals for their body size, and Palaeopropithecus
in particular has very small canals to match its reconstructed extremely
slow locomotion. (Some or all of these subfossil large Madagascan fossils
may have been aquarboreal. --MV) In some cases, canal size does not seem
to match expectations based on the locomotor behavioral classification. This
could occur when a small, unrepresentative sample falls toward the margins
of a species¹ morphological range of variation, especially when combined
with a less secure estimate of body mass. It may also be that locomotor
behavior was misclassified because certain aspects critical to the
perception of angular rather than linear motion were not recognized. A
possible example is Ateles geoffroyi, which is classified as medium in
agility, but its rather large canals fit well with its acrobatic behavior.
Importantly, the 3 canals do not necessarily express locomotor behavior in
equal measure, because this may depend on the planes of head motion
involved. For example, during hominin evolution only the anterior &
posterior canals enlarge with the emergence of modern-human-like bipedal
locomotion (2). In contrast, tarsiers & galagos on the one hand, and lorises
on the other are most distinct in lateral canal size. Likewise, the small
lateral canal of Alouatta seniculus is consistent with its less agile
behavior. However, its anterior canal appears unexpectedly large, possibly
the consequence of spatial constraints of the subarcuate fossa (24), which
opens into the endocranial cavity through the arc of the anterior canal, and
houses a lobule of the cerebellum. In all, the species that most strikingly
seem to contrast with the overall canalagility correlation are the 4
callitrichids. These are classified as agile, but their anterior & lateral
canals fall between the middle & lower end of the canal size distribution.
It is unclear why this is, and more work will need to be done to understand
the factors underlying this exceptional morphology. In nearly all cases, the
phylogenetic GLS models employing some type of branch length transformation
outperformed both the star phylogeny (conventional regression) and the GLS
method by using untransformed divergence times gathered from the literature.
Of the 3 branch length transformations used, Grafen¹s & Pagel¹s typically
performed best. The addition of well dated extinct species throughout our
phylogenetic tree will result in more accurate reconstructions of the
ancestral nodes, which in turn may then allow a better reconstruction of
the evolution of characters. Nevertheless, as was found here, transformed
trees may still perform better than those based on divergence times. This
may be for a variety of reasons, including the presence of unavoidable
measurement error in the estimates of species¹ mean BM and canal radii (25).
The similarity of results between the conventional and the phylogenetic
regression models indicates that the SCC system holds a very strong
functional signal related to head motion & locomotor agility. Such an
apparently robust functional relationship across primates & other mammals
suggests that adjusting arc size, and thus endolymph circuit length,
constitutes a prime adaptive mechanism of how the canal system is tuned to
the kinematic characteristics of different locomotor repertoires. This
finding will contribute to a more fundamental understanding of the
biomechanics of the canal system. On a more practical level, it confirms the
potential utility of the SCCs for the reconstruction of behavior from fossil
specimens.
From suppl.text:
... 86 Ma for Primates/Scandentia-Dermoptera (Springer et al.).
... 77 Ma for Strepsi/Haplorhine split ...
The base of Strepsirrhines at 69 Ma (Yoder & Yang)
the base of Lorisiformes at 55 Ma,
the base of Lemuriformes at 62.7
... Afr./As.lorises was set at 42 Ma
... Galagoides/Galago-Otolemur clade was set to 30 Ma
The base of the Haplorhines was set at 55 Ma (Ross et al.) based on the
presence of Tarsius eocaenus at 45 Ma.
... platy/catarrhine is placed at 43.6 Ma (Eizirik et al.).
The base of the platyrrhine radiation is set at 25 Ma based on the initial
appearance of platyrrhines in the fossil record during the early Mio. The
presence in the Miocene of fossils purported to belong to modern clades
suggests a rapid radiation of known clades after 25 mya.
... cercopith/hominoid split was placed at 34.7 Ma (Yoder & Yang), which is
similar to other estimates (15).
The phylogeny of hylobatids was based on Roos & Geissmann, & the divergence
dates were arbitrary following the 15 Ma split with hominids (sensu
hominids+pongids --MV).
The divergence dates within hominids were based on Stauffer et al.
Information & reasonable speculation on mammal and human hearing and its relationship to ancestral human foraging.
Me: Both the cuboctahedron (VE) and the icosahedron have equidistant vertexial nodes. An icosahedral sphere can be divided into 31 equilateral great circles [circumscribed icosahedral geodesic sphere] associated with 12 vertexial nodes, the human body has 31 spinal nerve pairs associated with 12 cranial nerves, and an octave can be split equally into 31 pleasing tones and as well the 12 notes of the major scale.
Per Rybo: Archimedes 4-fold asymmetrical cubo-octahedral (VE)-- is defined by 4 Great Circles) and has 8 equilateral triangles composed of 24 chords (3 x 8 = 24)
The VE also can be conceptually spun (or centrally split) to create 25 primary Great Circles.
The 25 Great Circle's will subdivide the VE's spherical surface.
Plato's 5-fold symmetrical Icosahedron can be conceptually spun (or centrally split) to have 31 primary Great Circles. 10 of the Icosahedrons 31 Great Circles will function to define five different 4-fold, 4 Great Circles of the VE.
Rybo
Please see this site on spinal & cranial nerves (click on pic):
http://tinyurl.com/2ma6by
DM: "Lots of people believe that the human menstrual cycle is somehow coupled to the moon."
Me: Yes, for good reason I'm sure. The vast majority of life on Earth dances to the solar-lunar-tidal cycle dance.
http://www.kingsoutdoorworld.com/hunting-guide/deer_activity.htm#BEST%20FISHING%20DAYS
Fishermen and hunters tend to follow the solunar cycles when crepuscularly active, whether or not they are actually at the tideline. Our ancestors were no doubt far more in tune with the lunar tidal flows than modern humans in urban areas are. While the women bled safely either at seashores or in caves (not moving around in the woods or the bush), the men would hunt and fish without distractions.
DM: "They overlook two very important things: firstly, the 29-day duration of the menstrual cycle is an average of a range of several days, and secondly, the human menstrual cycle is just that -- human".
Me: Apes also have similar estrus cycles, hylobats (gibbons, siamangs) (and possibly orangutans?) are quite close to humans cycles also, while chimps and gorillas have been away from the tidal effect due to being more inland, so their cycle has changed, becoming more terrestrial (monkey-like).
DM: "Rats have a cycle of 11 days. Chimpanzees have one that is a bit longer than the human one. Why should of all mammals we be coupled to the moon?"
Me: Both sun and moon. Our bodies' extra-cellular fluids have a salinity level of 9ppt, in between the Baltic sea and the Black sea, approximately estuarine, with pH level similar to seawater, we "are" the sea. However I can't answer your question without mentioning that our ancestors spent much time at the tidal shores foraging. If you picture our ancestors just swinging around and then dashing about on the splendid savannah with the little kitty cats, then I don't think you would be interested in my seashore speculations.
DM: "I think you have likewise merely found a coincidence. In keeping with this, not even all mammals have the same number of vertebrae and therefore spinal nerve pairs".
Me: The numbers 31 and 12 pop up together in "unexpected coincidental" correlations. If humans are the least derived physically, most derived mentally, from the primitive mammalian condition, then 12 and 31 might be of great significance. Need more data though.
DM: "I forgot... 31 pleasing tones? Can it get more subjective than that?"
Me: Please see this article:
http://www.mooremusic.org.uk/kcm/et31.htm
DM: "Not just among humans. Not all ears are human. Bird ears, for example, are quite different from mammal ears -- their high pitch limit is below the mammalian one (though above the one we humans actually reach), but they can discriminate more tones within the same frequency range. Pleasing or not, they'd vehemently disagree with "31"."
Me: I'd assume that most insectivorous birds would have excellent pitch determination. Cave swifts use non-target echolocation. I don't know the jaw-ear configuration in birds, dino, pterasaurs, marine reptiles, would be interesting comparisons.
(DM above is David M. who left comments in "What Thumb?" post, the unedited dialog is found at Tetrapod Zoology Science Blog, Dinosaur feathers II)
Tetrapod Zoology
Dinosaur-mammal info: click here
195ma "shrew" Hadrocodium ancestor of placentals? mammal ears
http://www.sciam.com/article.cfm?articleID=00044924-E7BC-1C5E-B882809EC588ED9F
125ma "newt-like?" Yanoconodon near-mammal ears semi-aquatic?
http://www.sciam.com/article.cfm?articleid=527675D9-E7F2-99DF-3265F1A19B72042F&chanId=sa027
125ma "opossum" Eomaia
http://www.sciam.com/article.cfm?articleID=000F30B7-117C-1CD0-B4A8809EC588EEDF
81ma - 55ma? "mouse-lemur-like" Oldest LCA primates
http://www.sciam.com/article.cfm?articleID=00094DEC-0E75-1CD0-B4A8809EC588EEDF
42ma Texas coast lagoon primates
http://news.yahoo.com/s/ap/20070402/ap_on_sc/texas_primates_1
Ancient human divers: jaws, hearing, vocalizing, ear exostosis
http://forums.deeperblue.net/beach-bar/70765-ancient-divers-ears.html
DDeden
http://info.uu.se/press.nsf/pm/did.our.idF2D.html
Mystery Of Mammalian Ears Solved
http://www.sciencedaily.com/releases/2007/07/070727172839.htm
A 30-year scientific debate over how specialized cells in the inner ear
amplify sound in mammals appears to have been settled more in favor of
bouncing cell bodies rather than vibrating, hair-like cilia, according to
investigators at St. Jude Children's Research Hospital.
The finding could explain why dogs, cats, humans and other mammals have such
sensitive hearing and the ability to discriminate among frequencies. The
work also highlights the importance of basic hearing research in studies
into the causes of deafness.
"Our discovery helps explain the mechanics of hearing and what might be
going wrong in some forms of deafness," said Jian Zuo, Ph.D., the paper's
senior author and associate member of the St. Jude Department of
Developmental Neurobiology. "There are a variety of causes for hearing loss,
including side effects of chemotherapy for cancer. One strength of St. Jude
is that researchers have the ability to ask some very basic questions about
how the body works, and then use those answers to solve medical problems in
the future."
The long-standing argument centers around outer hair cells, which are
rod-shaped cells that respond to sound waves. Located in the fluid-filled
part of the inner ear called the cochlea, these outer hair cells sport tufts
of hair-like cilia that project into the fluid. The presence of outer hair
cells makes mammalian hearing more than 100 times better than it would be if
the cells were absent.
As sound waves race into the inner ear at hundreds of miles per hour, their
energy--although dissipated by the cochlear fluid--generates waves in the
fluid, somewhat like the tiny waves made by a pebble thrown into a pond.
This energy causes the hair cell cilia in both mammals and non-mammals to
swing back and forth quickly in a steady rhythm.
In mammals, the rod-shaped body of the outer hair cell contracts and then
vibrates in response to the sound waves, amplifying the sound. In a previous
study, Zuo and his colleagues showed that a protein called prestin is the
motor in mammalian outer hair cells triggers this contraction. And that is
where the debate begins.
While both mammals and non-mammals have cilia on their outer hair cells,
only mammalian outer hair cells have prestin, which drives this cellular
contraction, or somatic motility. The contraction pulls the tufts of cilia
downward, which maximizes the force of their vibration. In mammals, both the
cilia and the cell itself vibrate. Thus far the question has been whether
the cilia are the main engine of sound amplification in both mammals and
non-mammals.
One group of scientists believes that somatic motility in mammalian outer
hair cells is simply a way to change the height of the cilia in the fluid to
maximize the force with which the cilia oscillate. That, in turn, would
amplify the sound. An opposing group of scientists maintains that although
the vibration of the outer hair cell body itself--somatic motility--does
maximize the vibration of the cilia, the cell body works independently of
its cilia. That is, vibration of the mammalian cell dominates the work of
amplifying sound in mammals.
"If somatic motility is the dominant force for amplifying sound in mammals,
this would mean that prestin is the reason mammals amplify sound so
efficiently," Zuo said.
In the current study, Zuo and his team conducted a complex series of studies
that showed in mammals that the role of somatic mobility driven by prestin
is not simply to modify the response of the outer hair cells' cilia to
incoming sound waves in the cochlea fluid. Instead, somatic motility itself
appears to dominate the amplification process in the mammalian cochlea,
while the cilia dominate amplification in non-mammals.
Zuo's team took advantage of a previously discovered mutated form of prestin
that does not make the outer hair cells contract in response to incoming
sound waves as normal prestin does. Instead, the mutated form of prestin
makes the cell extend itself when it vibrates.
The St. Jude researchers reasoned that if altering the position of the cilia
in the fluid changes the ability of the cilia to amplify sound, then hearing
should be affected when the mutant prestin made the cell extend itself.
Therefore, the team developed a line of genetically modified mice that
carried only mutant prestin in their outer hair cells. The researchers then
tested the animals' responses to sound.
Results of the studies showed no alteration in hearing, which suggested that
it did not matter whether the outer hair cells contracted or extended
itself, that is, raised or lowered the cilia. There was no effect on
amplification. The researchers concluded that somatic motility was not
simply a way to make cilia do their job better; rather, there is no
connection between the hair cell contractions and how the cilia do their
job. Instead, somatic motility, generated by prestin, is the key to the
superior hearing of mammals.
A report on this work appears in the advanced online issue of "Proceedings
of the National Academy of Science."
Other authors of this study include Jiangang Gao, Xudong Wu and Manish Patel
(St. Jude); Xiang Wang, Shuping Jia and David He (Creighton University,
Omaha, Neb.); Sal Aguinaga, Kristin Huynh, Keiji Matsuda, Jing Zheng,
MaryAnn Cheatham and Peter Dallos (Northwestern University, Evanston, Ill.).
[From DB or AAT? dive down past the spherical harmony section if you like]
Regarding hearing, humming and spherical/planar/scalar harmony
Semi-circular ear canals in mammals, primates
The primate semicircular canal system and locomotion
Fred Spoor, Theodore Garland Jr, Gail Krovitz, Timothy M Ryan, Mary T Silcox
& Alan Walker 2007
The semicircular canal system of vertebrates helps coordinate body
movements, including stabilization of gaze during locomotion. Quantitative
phylogenetically informed analysis of the radius of curvature of the three
semicircular canals in 91 extant and recently extinct primate species and
119 other mammalian taxa provide support for the hypothesis that canal size
varies in relation to the jerkiness of head motion during locomotion.
Primate and other mammalian species studied here that are agile and have
fast, jerky locomotion have significantly larger canals relative to body
mass than those that move more cautiously.
From the discussion:
... The strong relationship between SCC.size & locomotor agility is clearly
evident in a variety of primate groups. The leaping tarsiers & galagos have
large canals relative to their body size, whereas the slow quadrupedal
lorises, although of similar body size, lie on the lower end of the
distribution with relatively small canals. At larger body masses, this
relationship also holds. The acrobatic brachiating gibbons have rel.large
canals for their body size, compared with the great apes. The sloth lemurs
& koala lemurs have small canals for their body size, and Palaeopropithecus
in particular has very small canals to match its reconstructed extremely
slow locomotion. (Some or all of these subfossil large Madagascan fossils
may have been aquarboreal. --MV) In some cases, canal size does not seem
to match expectations based on the locomotor behavioral classification. This
could occur when a small, unrepresentative sample falls toward the margins
of a species¹ morphological range of variation, especially when combined
with a less secure estimate of body mass. It may also be that locomotor
behavior was misclassified because certain aspects critical to the
perception of angular rather than linear motion were not recognized. A
possible example is Ateles geoffroyi, which is classified as medium in
agility, but its rather large canals fit well with its acrobatic behavior.
Importantly, the 3 canals do not necessarily express locomotor behavior in
equal measure, because this may depend on the planes of head motion
involved. For example, during hominin evolution only the anterior &
posterior canals enlarge with the emergence of modern-human-like bipedal
locomotion (2). In contrast, tarsiers & galagos on the one hand, and lorises
on the other are most distinct in lateral canal size. Likewise, the small
lateral canal of Alouatta seniculus is consistent with its less agile
behavior. However, its anterior canal appears unexpectedly large, possibly
the consequence of spatial constraints of the subarcuate fossa (24), which
opens into the endocranial cavity through the arc of the anterior canal, and
houses a lobule of the cerebellum. In all, the species that most strikingly
seem to contrast with the overall canalagility correlation are the 4
callitrichids. These are classified as agile, but their anterior & lateral
canals fall between the middle & lower end of the canal size distribution.
It is unclear why this is, and more work will need to be done to understand
the factors underlying this exceptional morphology. In nearly all cases, the
phylogenetic GLS models employing some type of branch length transformation
outperformed both the star phylogeny (conventional regression) and the GLS
method by using untransformed divergence times gathered from the literature.
Of the 3 branch length transformations used, Grafen¹s & Pagel¹s typically
performed best. The addition of well dated extinct species throughout our
phylogenetic tree will result in more accurate reconstructions of the
ancestral nodes, which in turn may then allow a better reconstruction of
the evolution of characters. Nevertheless, as was found here, transformed
trees may still perform better than those based on divergence times. This
may be for a variety of reasons, including the presence of unavoidable
measurement error in the estimates of species¹ mean BM and canal radii (25).
The similarity of results between the conventional and the phylogenetic
regression models indicates that the SCC system holds a very strong
functional signal related to head motion & locomotor agility. Such an
apparently robust functional relationship across primates & other mammals
suggests that adjusting arc size, and thus endolymph circuit length,
constitutes a prime adaptive mechanism of how the canal system is tuned to
the kinematic characteristics of different locomotor repertoires. This
finding will contribute to a more fundamental understanding of the
biomechanics of the canal system. On a more practical level, it confirms the
potential utility of the SCCs for the reconstruction of behavior from fossil
specimens.
From suppl.text:
... 86 Ma for Primates/Scandentia-Dermoptera (Springer et al.).
... 77 Ma for Strepsi/Haplorhine split ...
The base of Strepsirrhines at 69 Ma (Yoder & Yang)
the base of Lorisiformes at 55 Ma,
the base of Lemuriformes at 62.7
... Afr./As.lorises was set at 42 Ma
... Galagoides/Galago-Otolemur clade was set to 30 Ma
The base of the Haplorhines was set at 55 Ma (Ross et al.) based on the
presence of Tarsius eocaenus at 45 Ma.
... platy/catarrhine is placed at 43.6 Ma (Eizirik et al.).
The base of the platyrrhine radiation is set at 25 Ma based on the initial
appearance of platyrrhines in the fossil record during the early Mio. The
presence in the Miocene of fossils purported to belong to modern clades
suggests a rapid radiation of known clades after 25 mya.
... cercopith/hominoid split was placed at 34.7 Ma (Yoder & Yang), which is
similar to other estimates (15).
The phylogeny of hylobatids was based on Roos & Geissmann, & the divergence
dates were arbitrary following the 15 Ma split with hominids (sensu
hominids+pongids --MV).
The divergence dates within hominids were based on Stauffer et al.
Information & reasonable speculation on mammal and human hearing and its relationship to ancestral human foraging.
Me: Both the cuboctahedron (VE) and the icosahedron have equidistant vertexial nodes. An icosahedral sphere can be divided into 31 equilateral great circles [circumscribed icosahedral geodesic sphere] associated with 12 vertexial nodes, the human body has 31 spinal nerve pairs associated with 12 cranial nerves, and an octave can be split equally into 31 pleasing tones and as well the 12 notes of the major scale.
Per Rybo: Archimedes 4-fold asymmetrical cubo-octahedral (VE)-- is defined by 4 Great Circles) and has 8 equilateral triangles composed of 24 chords (3 x 8 = 24)
The VE also can be conceptually spun (or centrally split) to create 25 primary Great Circles.
The 25 Great Circle's will subdivide the VE's spherical surface.
Plato's 5-fold symmetrical Icosahedron can be conceptually spun (or centrally split) to have 31 primary Great Circles. 10 of the Icosahedrons 31 Great Circles will function to define five different 4-fold, 4 Great Circles of the VE.
Rybo
Please see this site on spinal & cranial nerves (click on pic):
http://tinyurl.com/2ma6by
DM: "Lots of people believe that the human menstrual cycle is somehow coupled to the moon."
Me: Yes, for good reason I'm sure. The vast majority of life on Earth dances to the solar-lunar-tidal cycle dance.
http://www.kingsoutdoorworld.com/hunting-guide/deer_activity.htm#BEST%20FISHING%20DAYS
Fishermen and hunters tend to follow the solunar cycles when crepuscularly active, whether or not they are actually at the tideline. Our ancestors were no doubt far more in tune with the lunar tidal flows than modern humans in urban areas are. While the women bled safely either at seashores or in caves (not moving around in the woods or the bush), the men would hunt and fish without distractions.
DM: "They overlook two very important things: firstly, the 29-day duration of the menstrual cycle is an average of a range of several days, and secondly, the human menstrual cycle is just that -- human".
Me: Apes also have similar estrus cycles, hylobats (gibbons, siamangs) (and possibly orangutans?) are quite close to humans cycles also, while chimps and gorillas have been away from the tidal effect due to being more inland, so their cycle has changed, becoming more terrestrial (monkey-like).
DM: "Rats have a cycle of 11 days. Chimpanzees have one that is a bit longer than the human one. Why should of all mammals we be coupled to the moon?"
Me: Both sun and moon. Our bodies' extra-cellular fluids have a salinity level of 9ppt, in between the Baltic sea and the Black sea, approximately estuarine, with pH level similar to seawater, we "are" the sea. However I can't answer your question without mentioning that our ancestors spent much time at the tidal shores foraging. If you picture our ancestors just swinging around and then dashing about on the splendid savannah with the little kitty cats, then I don't think you would be interested in my seashore speculations.
DM: "I think you have likewise merely found a coincidence. In keeping with this, not even all mammals have the same number of vertebrae and therefore spinal nerve pairs".
Me: The numbers 31 and 12 pop up together in "unexpected coincidental" correlations. If humans are the least derived physically, most derived mentally, from the primitive mammalian condition, then 12 and 31 might be of great significance. Need more data though.
DM: "I forgot... 31 pleasing tones? Can it get more subjective than that?"
Me: Please see this article:
http://www.mooremusic.org.uk/kcm/et31.htm
DM: "Not just among humans. Not all ears are human. Bird ears, for example, are quite different from mammal ears -- their high pitch limit is below the mammalian one (though above the one we humans actually reach), but they can discriminate more tones within the same frequency range. Pleasing or not, they'd vehemently disagree with "31"."
Me: I'd assume that most insectivorous birds would have excellent pitch determination. Cave swifts use non-target echolocation. I don't know the jaw-ear configuration in birds, dino, pterasaurs, marine reptiles, would be interesting comparisons.
(DM above is David M. who left comments in "What Thumb?" post, the unedited dialog is found at Tetrapod Zoology Science Blog, Dinosaur feathers II)
Tetrapod Zoology
Dinosaur-mammal info: click here
195ma "shrew" Hadrocodium ancestor of placentals? mammal ears
http://www.sciam.com/article.cfm?articleID=00044924-E7BC-1C5E-B882809EC588ED9F
125ma "newt-like?" Yanoconodon near-mammal ears semi-aquatic?
http://www.sciam.com/article.cfm?articleid=527675D9-E7F2-99DF-3265F1A19B72042F&chanId=sa027
125ma "opossum" Eomaia
http://www.sciam.com/article.cfm?articleID=000F30B7-117C-1CD0-B4A8809EC588EEDF
81ma - 55ma? "mouse-lemur-like" Oldest LCA primates
http://www.sciam.com/article.cfm?articleID=00094DEC-0E75-1CD0-B4A8809EC588EEDF
42ma Texas coast lagoon primates
http://news.yahoo.com/s/ap/20070402/ap_on_sc/texas_primates_1
Ancient human divers: jaws, hearing, vocalizing, ear exostosis
http://forums.deeperblue.net/beach-bar/70765-ancient-divers-ears.html
DDeden
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[This post is under construction, beware of detouring thoughts, meandering meanings...]
DM: Hearing in water is not the same as sonar, just like hearing in air is not the same as sonar -- bats have sonar, we don't.
DD: False. Sonar uses echoes of sound energy waves (in water or air) to determine relative position in the same way that vision does using light energy. As in a blind person with cane or oral clicking. Google.
The tiny inner ear cells in humans are hair cells (cilia per DM), derived from the anterior sensory hair cells of the lateral line in fish. Yes, it has something to do with water, sound energy frequencies (vibrations) provide information about the environment, likely these hairs had once been external vibrissae for the crustacean-fish last common ancestor.
However, I was speaking of the middle ears, the little bones and eustachian tubes to the nasal cavity. A human non-scuba diver can submerge and allow seawater into the nasal cavity and middle ears (in order to avoid gas-equalization problems at depth), while the soft palate separates the nasal cavity from the oral cavity.
Notably sound is then magnified (increased sound conduction via bones and dissonance is reduced) at depth, as compared to having air filled middle ears, since there is electrolytic liquid in the inner ears, middle ears, and external ears. Thus humans retain a weak form of sonar capability, though far inferior to that of the specialized fish chasing dolphins.
DD: Dive-Song is simply the brief description of the causative agent for many "special" traits of humans. White eyes (enlarged sclerae), monogamy, reduced size dimorphism compared to apes, singing, humming, clicking, music, epicanthal eyelids, primitive pinnae, unusual breathing adaptations, photic sneezing, eating raw shellfish, gift-giving-trade, sustained vocal communication, facial gestures, much reduced laryngeal air sacs compared to similar sized apes, etc. etc.
Speculative zoology? Yes, but strongly correlative biology and ecology and anthropology (when not dismissed by savanna-centered theorists). Does Dive-Song answer all the questions? No just a few of the hardest.
Savanna woodlands were occupied by humans much much later, after development of dug-out boats and tools allowed safe passage inland, previous to that trees and cliffs provided the only refuge from large predators, producing the arboreal apes. Tropical rainforests inland were obviously not where humans diverged from other apes. Anything which places ancient human ancestors 7-1ma long distances away from the shores (previous to boats) adds complexity (abundant sweating = needs abundant salt + water, freshwater not enough).