More thoughts on the AAH definition from Marc Verhaegen

11-Nov-2004

"AAT proposes that water has acted as an agent of selection in the evolution
of humans (Homo) more than it has in that of chimpanzees (Pan), and that
many of the major physical differences between humans and the other apes may
be explained, in part, as adaptations to moving better through various
aquatic media (wading, swimming and/or diving) and from greater feeding on
aquatic and waterside resources."

We certainly need Homo in the definition: AAT sensu stricto is about Homo,
has nothing to do with apiths.

I'd prefer this: "AAT proposes that human ancestors, during a certain period
after the Homo/Pan split, spent an important part of their day in water,
wading, swimming and diving, and feeding on aquatic and waterside foods."
(why make it longer than necessary?)

This is a minimalistic definition: I'd be more explicit (& more debatable):

"The Aquarboreal Ape Theory proposes that most Miocene hominoids lived in
coastal/swamp forests, and that Homo, after the Homo/Pan split, became
seaside omnivores that once fed predominantly on aquatic and waterside
foods."

If more details are needed, I propose our scenario, of course:

- Aquarboreal Apes Theory of hominoid evolution: "Hominids (chimpanzees,
humans and gorillas) and pongids (orangutans) split in the Miocene. A
climbing-plus-wading lifestyle in coastal or swamp forests, where most
Miocene hominid-pongid fossils are found, helps explain how they (starting
from a more monkey-like body build with narrow thorax and above-branch
locomotion) lost the tail, became much larger, and developed arm-hanging for
below-branch locomotion."

- Amphibious Ancestors Theory of Homo evolution (AAT sensu stricto):
"Plio-Pleistocene human ancestors were sea-side omnivores during a certain
period after the Homo/Pan split. A lifestyle of beach-combing, wading,
swimming, collecting coconuts, shellfish, turtles and turtle eggs, bird
eggs, crabs, seaweeds etc. explains many Homo traits (absent in Pan) much
better than dry savanna scenarios do: very large brain, greater breathing
control and diving skills, smaller mouth and masticatory reduction (myosine
MYH16), well-developed vocality, external nose, extreme handiness and tool
use, reduction of climbing skills, reduction of fur, more subcutaneous fat,
very long legs, more linear body build, reduction of olfactory sense, late
puberty, high needs of iodine, sodium and poly-unsaturated fatty acids, etc.
and in archaic Homo, pachyostosis, auditory exostoses, platycephaly, etc."