Re: AAT Questions...

Elaine Morgan (
Fri, 14 Jul 1995 18:40:46 GMT

Replies to various:...

J.D. Moore asks where did anybody see a film of bonobos wading
bipedally? I personally made a video film about AAT which included
two or three shots of them doing just that, and a couple os shots of
them walking upright on land in the forest, one behind
the other. I was allowed to use those shots on condition the film was
not shown commercially, only for e.g.seminars. I showed it once in San
Francisco. Copies for US video are available (can I say this? I am
assured that the charge is no more than enough to cover reproduction
and postage) from Ralph Metzner, 18210 Robin Avenue, Sonoma, CA
95476. I get nothing, okay?

J. Rhiemeier writes:

"Australopthecus did walk upright, no doubt. But it neither had
downward facing nostrils, and it was almost as hairy as a chimpanzee.

Okay, let's talk nostrils. There is no evidence whether it did or did
not have downward facing ones. As we see in the proboscis monkey, a
downwrd projection in the fleshy part can precede - or exist without -
any change in the skull. (Female and young proboscis have it too,
though far less pronounced). By the time of erectus an actual nasal
spine had evolved. (I had thought it earlier, this was what I was wrong
about as I am frequently reminded). This ossified nasal spine was most
probably a consolidation of a previous more perishable cartilaginous
version, comparable with the septum in modern Homo. It suggests that
something unusual had been happening to the nose for quite a long time;
in erectus's day it had been established long enough to need a skeletal
structure to underwrite it. If elephants were extinct and we could only
reconstruct them from the bones of the skull, who would be clever
enough to know what a trunk looked like?

And how can you say that austropiths were nearly as hairy as a chimp? A
purely arbitrary assertion. You would like to think they were.

Re Tattersall: I do not believe that the shape of the skull can tell us
anything about the respiratory canal. The pharyngeal space was enlarged
not by altering the shape of the skull but by the larynx sliding down
to below the back of the tongue.

Tears, idle tears... If anyone can find an ape that weeps from grief, I
will eat my computer. The innervation is totally different..

Rates of evolution. These are not hard figures. It is fairly meningless
to say one million years is three species' worth of evolution, because
even the term species is a man-made convenience. There is no place you
can draw a line between one species and its successor. Sombody (it may
have been Haldane?) invented the term "darwin" to measure how fast a
species evolved, but it has never come into use. When an animal evolves
too many things change simultaneously, there is no agreement about
which are the most important ones and no way of quantifying the net

We can only say we have the impression that since 7mya the homo line
has moved further away from the l.c.a. than the apes have done. i.e.
our anncestors developed faster. Two factors are known to favour rapid
spciation (1) geographic isolation, absolute enough to preclude
interbreeding - (2) a sudden marked change in the habitat. Compare AAT
and savannah mosaic. Which best accounts for (1)? Which best accounts
for (2)? Yes, I've heard of sympatric speciation - a very rare event
though compared to being cut off, as the Congo cut the chimps off from
the bonobo.

Elaaine Morgan