Wednesday, April 22, 2009

From sit-float-feeding to backfloat-dive-feeding to boat-net-feeding

AAT ~20ma initiation, 5ma immersion, 2ma dive/backfloating

I've no argument with Hardy's 20ma and Filler's date of ~20ma as initial aquatic
era, in an evolutionary sense. Upright posture, proconsul/morotopith wetland
sit-float-feeding as a change from its predecessor of upright dry sitting
(geladas) indicates daily aquatic foraging (surface feeding with gradually
enlarging air sacs and shrinking tail, maintained even in today's lowland
Homo Genus 5ma developing estuarine submersion foraging (crouch plucking), 3ma
seashore diving, 1.5ma diving/backfloating ARC cycle around the Levant and
former peri/tethys and upper Rift, gradual increase in waterside group ambush
improved tool technologies, which eventually took them to cooler rougher
predator-filled waters where rafts and boats were advantageous.
This from PZ's blog:
"As usual, it starts on a sound foundation of confirmed, known evidence, makes a reasonably hypothesis on the basis of the facts, and then proposes a series of research avenues with predicted results that would confirm the idea."

Non-scientists take note: this is a category of paper that is usually titled "hypothesis" or "insight," as opposed to a peer-reviewed research paper or a literature review, although it is more similar to the latter. PLoS Biology uses the term "unsolved mystery:"

Unsolved Mysteries discuss a topic of biological importance that is poorly understood and in need of research attention.

Re: From sit-float-feeding to backfloat-dive-feeding to boat-net-feeding

PAs can argue forever about details when evidence is scattered and lacking, and
topography and climate changes at varying rates.

I've produced a simple explanation, of how hominoids differentiated from other
primates (tail loss, air sacs), how Homo differentiated from other hominids (ARC
diving, low UV saltwater backfloating), and how Homo sapiens differentiated from
other Homo (mass harvesting -> trade -> transport).

Of the question 'What happened?' the missing pieces of the puzzle have been
found and placed, they fit.

Other explanations for the unique characteristics of humans compared to our genetic kin fall short by not taking into account various behaviors and vestigial traits common to humans but not to other primates. That doesn't mean they are insignificant or incorrect, just incomplete.

The story is a bit more complete now.

Prose of human speciation

Hominoids vs other primates (sit/float/eat, tail loss, air sacs),

Homo vs other hominids (ARC diving, low UV saltwater backfloating),

Homo sapiens vs other Homo (mass harvesting/transport).


Hominoids sit/floating on flooded ground,
hands to pluck/peel/pull/pinch,
calls/splashes/thumps to warn,
sleep in tree hollows, forks (damp), beaver dens
eat meat without bones (eggs, pith, larvae, seeded fruit)

Homo going deeper into water/caves, while apes went higher,
Homo crafted long/sharp fangs/claws of sticks/stones/shells.
Using pebbles to crack, flakes to cut, bifacials to bait, branches to bash,
spears to probe/pry/poke, lords of the ring/pond/pool
eat meat/nuts with shells/bones to be removed and reused.

Hs brought sunlight into cold night (fire),
and dark into hot day (shelter), and wet into dry.
Bags/baskets/boats processed (cut, woven) to transport, harpoons/atlatls to
launch spears/darts.
Meats/grains to guide/process (planting/herding), grinding masses, soaking,
heating, storing, exchanging, comparing.
Rings concentrically ordered, become overly congested and condense into
rectilinear patterns and vertical double-storied dwellings and overlapped social
groupings and finally oral-named individuals become anonymously writ-numbered
cells in the spherical body of humankind and beyond.

Compare these two shelters: entry routes, protection from bears/cold

Mammoth bone lodge of Central Russian floodplain 15ka, summer doorway

22ka camp huts & bedding at upper Rift waterside link

seal ancestors link


Thursday, April 16, 2009

Tuesday, April 7, 2009

Bio-convergent parallel: Anuroid & Hominoid

Arkive Video: Gorillas vertical wading and wet-sit-eating

left: dryland gelada, long-tailed, vertical-trunk, dry-sit-eat grasses, no air sac
right: lowland gorilla, tail-less, vertical-trunk, wet-sit-eat sedges, air sac

Another Video: Lowland Gorillas eating sedge rhyzomes and high-protein AHV (Aquatic Herbaceous Vegetation) while sitting-floating in forest open wetland Arkive video link

DD: The question is not "do air sacs always cause loss of tail?", but "is the complete loss of tail in hominoids due (in part) to laryngeal air sac?" The answer is clear, yes, float-sit-feeding with inflatable air sac selects for tail loss.

MV: Not so clear IMO: may depend on body size, size of airsacs, terrestrial vs aquatic milieu, salt vs fresh water milieu, time spent in trees & water, arm-hanging vs hopping vs above-branch, etc.

DD: parallel convergence at forest-waterside (swamp, wetland, shore):

left: Axlotl, long-tailed 'tadpole' with external gills and legs, swims but doesn't sit
right: Macaque, long-tailed, with lungs and legs, swims but doesn't feed sit-floating

Tadpoles with long tail swim, they don't sit partially feeding in water, they don't have prehensile tongue; frogs with no tail sit partially in water, and use long prehensile tongue to eat. Some frogs then evolved more arboreal traits (better climbing skills, less swimming), others spend much time on lake bottoms and developed more aquatic traits (skin 'gill' breathing)

left: tree frogs have since further specialized to arborealty, more 'spidery' and colorful
right: aquatic frog with hydrodynamic red external gills re-adapted to full submersion

Monkeys with long tails swim (Nasalis, Long-tailed macaque); while Ndoki swamp gorillas
(~LCA H-oid) with no tail sit partially in water while feeding.

left: tree apes have since further specialized to arborealty, more 'spidery' and colorful
right: aquatic apes (humans) with hydrodynamic hair re-adapted to submersion diving

AFAIK, neither spidery tree frogs nor deep-submersion frogs inflate their throat air sacs as much as forest-waterside frogs.

AFAIK, neither spidery tree apes (gibbon) nor deep submersion apes (humans) inflate their throat air sacs as much as forest-waterside apes.

Parallel pattern. Partial sit-float eating -> air sac -> tail lost; eventually species body size may enlarge at forest-waterside, OR become full-time spidery at arboreal canopy OR adapt deep submersion with active skin glands* or skin gills* as per photos.

DD: Complete loss of tail = vertical-trunk float-sitting while plucking-foraging. Laryngeal air sacs. Compare to long tailed gelada sitting while plucking-foraging grass on dry ground. No air sacs there, of course.

MV: Some baboons have short tails IIRC?

DD: None lost their tail, many highland monkeys (cold nights select for short tails) with non-prehensile tails have short tails. Tail covers peri-anal region, in water, muscle valves and tissue close peri-anal region.

Dry-sit-eating (no air sac, long-tailed) savanna gelada vs wet/float-sit-eating (air sac, tail-less) Ndoki swamp gorilla

* frogs and salamanders may respire via gills, lungs or skin. I conjecture that the eccrine skin glands of humans (inactive in African apes except volar eccrines) function in very limited respiration. link

Evolution Canyon European-African micro-climates in Jordan Rift Valley

Flowering plants & veination 140ma:
The study, by Dr Tim Brodribb and Dr Taylor Field of the University of Tasmania and University of Tennessee, used plant physiology to reveal how flowering plants, including crops, were able to dominate land by evolving more efficient hydraulics, or 'leaf plumbing', to increase rates of photosynthesis.

"Flowering plants are the most abundant and ecologically successful group of plants on earth," said Brodribb. "One reason for this dominance is the relatively high photosynthetic capacity of their leaves, but when and how this increased photosynthetic capacity evolved has been a mystery."

Using measurements of leaf vein density and a linked hydraulic-photosynthesis model, Brodribb and Field reconstructed the evolution of leaf hydraulic capacity in seed plants. Their results revealed that an evolutionary transformation in the plumbing of angiosperm leaves pushed photosynthetic capacity to new heights.

The reason for the success of this evolutionary step is that under relatively low atmospheric C02 conditions, like those existing at present, water transport efficiency and photosynthetic performance are tightly linked. Therefore adaptations that increase water transport will enhance maximum photosynthesis, exerting substantial evolutionary leverage over competing species.

Saturday, April 4, 2009

Aquanautical microbiota: Green Algae

Spirogyra reproduction, reminds one of double helix DNA, chromosome replication

Dancing spheres: volvox rotates, oscillates

Volvox reproduction, note the triangulation of cytoplasm threads, geodesic structure

volvox A large sphere colony with daughter sphere colonies containing small granddaughter colonies. Both male and female colonies form inside the equator of the parent colony. Volvoxes are hollow spheres of independent cells that each have an eye spot, the colony develops a light-polarity, where half of the colony has larger eye spots, making a supercell eyeball of sorts. Click the link to find out more. volvox wikipedia
nuther volvox tale

Pediastrum algae, a flat disk star

These outstanding photos are from this site: The Micropolitan Museum

Hydrodictyon reticulatum, Hexa-penta Water net algae, from: Hydrodictyon, Wikipedia

Protists: dinoflagellate plant/animal (planimal?) in toxic red tide, endosymbiont coral bleaching, some photosynthesizers and some with eyes (retina), have minicircles of 12 genes.

Marimo Moss balls (Chladophora)

from cell to super-cell organism to super-organism society: colonial ants

Nutrition: Seaweed gardens

Naturally growing seaweeds are an important source of food, especially in Asia. They provide many vitamins including: A, B1, B2, B6, niacin and C, and are rich in iodine, potassium, iron, magnesium and calcium.[50] In addition commercially cultivated microalgae, including both Algae and Cyanobacteria, are marketed as nutritional supplements, such as Spirulina,[51] Chlorella and the Vitamin-C supplement, Dunaliella, high in beta-carotene.

Algae are national foods of many nations: China consumes more than 70 species, including fat choy, a cyanobacterium considered a vegetable; Japan, over 20 species;[52] Ireland, dulse; Chile, cochayuyo.[53] Laver is used to make "laver bread" in Wales where it is known as bara lawr; in Korea, gim; in Japan, nori and aonori. It is also used along the west coast of North America from California to British Columbia, in Hawaii and by the Māori of New Zealand. Sea lettuce and badderlocks are a salad ingredient in Scotland, Ireland, Greenland and Iceland.
Dulse, a food.

The oils from some Algae have high levels of unsaturated fatty acids. For example, Parietochloris incisa is very high in arachidonic acid, where it reaches up to 47% of the triglyceride pool.[54] Some varieties of Algae favored by vegetarianism and veganism contain the long-chain, essential omega-3 fatty acids, Docosahexaenoic acid (DHA) and Eicosapentaenoic acid (EPA), in addition to vitamin B12. The vitamin B12 in algae is not biologically active. Fish oil contains the omega-3 fatty acids, but the original source is algae, which are eaten by marine life such as copepods and are passed up the food chain.[55] wikipedia: algae nutrition