re: evolution - AAT (Aquatic Ape theory)

J de Lyser (
Mon, 20 Jan 1997 21:06:57 +0100

John K Clark <> wrote

>But the important thing is the line of decent that uniquely led to humans, as
>opposed to some other animal. This line is much shorter than thought 20 years
>ago, it's only 5 or 6 million years old. That lends support to the idea that
>the Evolution of humans was not an inevitable outcome but a lucky accident.

True, but it's just as 'lucky' an accident that other species didn't develop
intelligence. Any omnivorous species with smalll gestation size, and
relatively long gestation time, theoretically could have. It was 'lucky'
that pre-homonids developed it, and not some other species with a similar
function in the ecosystem.

>On Sun, 19 Jan 1997 J de Lyser <> Wrote:
>>Correct me if i'm wrong, but there we're also no lions at the time of
>>Autralopethicus Afarensis.

>True, but there were plenty of other large fast carnivores, like the ancestor
>of lions and saber tooth tigers.

which ancestor of lions and sabertooth tiger ? name one big cat who lived 5
million years ago in africa !

Australopithicus Afarensis 4-5 mln years ago
Various Smilodon (sabertooth species) -> not in africa, only in america !

Homo Habilis/erectus (who used tools) 2mln years ago
Various Acinonyx species (cheetah like solitary hunter) only distributed
over the world between 3-1 million years ago.

Panthera atrox, the direct ancestor of the lion, who hunted in groups, never
developed until the time of homo erectus, and could be fought off with
spears and tools.

that leaves a very 'grey' area of discussion of about 1 million years (3-2
mln years ago) where a stupid, small and just developed acinonix species
might have preyed on a DESCENDANT of Afarensis who was 2 million years in
development already (2mln years in development BEYOND lucy, 1 mln years away
from Habilis), and probably had aquired more brain volume, use of primitive
tools etc.

On this 'grey' period:

Acinonyx species are generally smaller in body size/weight than panthera
species, and like smilodon, they were nowhere near as intelligent or as
sophisticated hunters as modern big cats (including modern acinonix: the
cheetah). Smilodon and early acinonyx, were stupid cats!

You were putting up chimps against modern predators, not prehistoric
homonids against prehistoric predators !

You were giving the ancestors of the modern big cats (panthera species
(tiger, lion) hadn't evolved yet) the qualities of their current
equivalents, and put them up against Afarensis. Allthough i agree that
hominids use their intelligence more than big cats, and the danger acynonix
posed to LATE Afarensis was probably greater than the danger that modern big
cats pose to modern man, i don't think it EQUALS the danger that MODERN big
cats (ie=Panthera genera) would pose to EARLY Afarensis.

again 3 million years ago the first succesful big cat: acinonyx just started
spreading, it found itself matched against a species of Australopithecus who
was 2mln years in development since lucy, and allthough he was no homo
habilis yet, he definitly was no chimp, whereas acynonix definitely was no
modern cheetah, let alone tiger or lion !!!

Again, more dangrous to Afarensis would have been hyenids, ofcourse also
underdeveloped, and not to be compared with todays hyena species, but they
hunt in packs, were not much smaller than acynonix, and in my opinion they
were the predator that 'aided' homonid evolution.

>There is not a particle of evidence that Australopithecus Afarensis engaged
>in hunting of any sort, but yes, it must have had some method of dealing with
>predators, because despite being slow and weak and having no tools, Lucy's
>kind not only survived they thrived. The mystery is why.

mystery solved: acinonyx was a kitten and hyenas can't climb trees ;-)

J. de Lyser