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



Knud Munk said...

You seem to adhere to the aquatic ape theory. I have read the recent contributions of Elaine Morgan. It seems nobody has investigated the theory in light of the rapidly increasing evidence derived from the study of the human genome. Have contributed to developing the theory? Also I would be interested in your opinion why AAH is given so little attention as it seems to me to be crucial in understand human evolution.

"the Dude" said...

After having looked at various interpretations of why humans are such uniquely different mammals, I realized that waterside habitat and foraging were far more significant than what the typical savanna stories being produced would indicate. It isn't easy to read the genome and match successful mutations timewise to fit with dated artifacts and fossils. Recent changes, such as lactose tolerance in Europeans, or reduced sweating in Ethiopeans, or tolerance to high altitude and low oxygen in Tibetans and Andeans happened <10ka. Earlier mutations are far harder to date and match with precision.

Technological evolution has tended to focus on tool use; savannas, caves and deserts tend to preserve fossils and stone tools well while cyclical sea level rises tend to destroy such evidence. Coastal paleoanthropological research has been increased since Hardy, Morgan, Verhaegen, Ellis, Fuller and others focused on abundant aquatic, littoral, seashore resources and corresponding inland constraints (Iodine, Omega 3, etc.) and comparative anatomical analyses.