Re: EVOLUTION: The Aquatic Ape

J de Lyser (
Sat, 25 Jan 1997 04:38:29 +0100 (Jay Reynolds Freeman) wrote:

>> [Discussion of size and existence of Tertiary predators]

> The fossil record for cats is not very complete, but the earliest,
>(family _Nimravidae_, not _Felidae_) appeared in the Early Oligocene
>(roughly 40 million years ago), with retractile claws and dentition
>like modern cats, with additionally some having "saber-like" upper
>canines. The book has an photograph of a complete fossil Oligocene
>sabertooth skeleton, length perhaps a bit more than a meter from nose
>to base of tail, and has drawings of skulls of several other Oligocene
>large-toothed cats, that size and a little larger; later ones were
>bigger still. This family lasted through the Pliocene. _Felidae_ --
>the family to which modern cats belong -- appeared in the Miocene, but
>later in the Miocene and in the Pliocene radiated into both
>saber-toothed and non-saber-toothed species; some saber-toothed
>_Felidae_ had skulls almost as large as those of modern lions.
>Saber-toothed _Felidae_ survived until the end of the Pleistocene, and
>may have coexisted with humans. "Saber teeth" are an adaptation that
>has occurred at least four separate times in mammals, likely as a
>specialized adaptation for killing large prey, likely by ambush.

Still this says very little about those Nimravidae, i know sabertooths were
big (fatalis WAS as big as a lion), i also know they were not very smart,
but more importantly, they didn't live in Africa. I know there must have
been a somewhat similar big cat in africa (the marks in the skulls). But i
found nothing about pre-panthera felidae in africa around 4 million yrs ago,
and this book doesn't tell me anything new, except the genera name of
Nimravidae (for which i thank you a lot). In my last posting i had already
assumed a smilodon like (slightly smaller, slightly more intelligent)
species, what's new is that it probably did have retractable claws, thats
all this adds. In order to compare the cats and match them with Afarensis,
one needs to know what their capabilities were, (unless we want to keep
comparing/matching chimps with cheetahs/leopards). From what i've seen so
far in this tread, if a group of chimps can handle a leopard, and (late)
afarensis was a tool user. Any predator cat, has to be a multitude more
dangerous than modern big cats, to form any real threath to the survival of
Afarensis as a species. And if the pro AAT group wants to talk about
pre-Australopithicenes, they'd be talking about apes, not hominids.

John Clark wrote:
>Bite marks made by Leopards have been found in many of the
>skulls of these animals,

I think we both agree it was a big cat, I just wan't you to realize that
todays big cats, are not the same as 3.5 million years old big cats. If YOU
believe in evolution, you have to acknowledge that even though the
improvements to these cats, are nowhere near the ones that appeared in
Hominids, there will have been improvements.

I'll tell you one thing, I've never heard
>of an ecosystem, past or present, that had prey species but no predators,
>and besides Lucy there were many other types of tasty meat running around,
>several varieties of pigs and a sort of dwarf hippopotamus among others.

I guess an ecosystem without predator species automatically excludes 'prey'
species, but i get your point. I think you're still looking at Afarensis as
a prey species by definition. Did any of my posting about the chimps being
able to handle the leopards get trough to you ? I think big cats did
occasionally grab an afarensis: a young one, an old or diseased one, or a
healthy one that they were able to single out, just like todays lion can
kill the occasional human. I still don't think afarensis was by definition a
'prey' species. Gestation size and time exclude that option, it would not
have been so widely spread if it was.

>I very much doubt that "all" were, but we do know that Lucy lived near a lake
>that was full of crocodiles.

It would be interesting to know how many and which ones lived in the red sea
at the time, and what evidence there is left in humans today that suggests
an Aquatic ape being capable of defending itself from attacks from the
water, and maybe also from under water.

>You're assuming that because we are enormously smarter than Lucy was then
>present day predators must be enormously smarter than the predators of
Lucy's day. It's not so.

Look up a picture of a smilodon skull - It's FLAT where the brain should be,
where todays big cats have much rounder skulls. Are you assuming all species
evolution stopped when the first hominids arrived ? We are talking about
predators that were less dangerous (to whatever degree), and possible prey
(maybe for a hominid predator) that was easier to catch (also to whatever
degree) than todays comparable species. If you look just at time i'd say
10%, if you look at relatively increasing developments (among all mammals,
not just hominids) i'd be tempted to say more than that.

>Yes, if you plotted the average brain size of all animals from the
>extinction of the Dinosaurs to now you would find a modest increase, but
>there is nothing modest that happened to the human line. The brains of our
>ancestors got almost 5 times as big in just 3 million years, and nothing
>even close to that has ever happened in Evolution before. This huge
>explosion in brain size started at the same moment we developed bipedalism
>and a hand that can make complex motions. I don't believe this is a
>coincidence, and that's why I think the bipedalism question is so important.

Many other homonid and homonoid species were bipedal, why didn't they
develop intelligence ? why did they become extinct instead, just because
there was one who was better ? I think maybe, more efficient bipedalism and
complex hand motion might be the result of intelligence increase, but it's
harder to believe it was the cause.

Crosby_M <> wrote:

>< Stone tools dating back 2.5 million years are the oldest ever found,
>scientists reported Wednesday, prompting a search for more evidence
>about the pre-humans who made them. The surprisingly sophisticated
>tools, found on the border between Ethiopia and Kenya, push back
>the frontier of the first-known use of tools by pre-humans by 200,000

Did it say if it was found alongside habiles skeletons or among afarensis ?

Again i'd like to try to end the predator part of the AAT, seen the example
of the chimps beating up/killing the leopards. I think it says it all, and i
assume there's no one who had arguments against that one ?

That way i can orientate myself on the bipedalism part of the tread a little...

J. de Lyser