Re: chimps on the savanna? Nooooo.....

Alex Duncan (aduncan@mail.utexas.edu)
2 Nov 1995 03:17:19 GMT

"...one thing for sure, I'd never make such cocksure statements as those
made by some when the evidence for it is so little."

Hubey, 6 Oct, 1995

Once again, the issue here is getting obscured, largely by Hubey's well
developed obfuscatory tactics. The original post was a response to
Hubey's claim that chimps don't go onto the savanna.

"Repeatedly, lions don't hang around forests, and chimps don't hang
around the plains."

Hubey, 10 Oct, 1995

And, in response to the suggestion that the earliest hominids were
basically chimp-like animals who were living in slightly more open
environments:

"As soon as they leave the trees they're sitting ducks. They couldn't
find food let alone escape predators."

Hubey, 5 Oct, 1995

The issue is not how we define "savanna" or "plains." The issue is
fundamentally this (divided into two parts):

1) Are chimps a good behavioral analogy for the earliest hominids?

2) Can chimps survive in open country? (The implication being that if
chimps can do it, the earliest hominids could have done it.)

Unfortunately, we can not answer the first question as precisely as we
might like. The answer is that chimps are probably the best analogy
available to us (given similarities in body size and morphology), but
that we must remember the differences between the earliest hominids and
chimps.

We can answer the second question. Hubey seems to think the answer to
the second question is "no -- chimps can't survive in open country",
which is why I posted the original abstract. Here it is again:

McGrew WC, Baldwin PJ & Tutin CEG (1981) Chimpanzees in a hot, dry and
open habitat: Mt. Assirik, Senegal, West Africa. J. Hum. Evol.,
10:227-244.

Begin quote

The habitat of the chimpanzees of Mt. Assirik, in the Parc National du
Niokolo-Koba, Senegal, is described in terms of rainfall, temperature and
vegetation. The results are compared with those collected at five other
sites of study elsewhere in Africa. Mt. Assirik is the driest site at
which chimpanzees have been studied, in terms of annual rainfall,
proportion of dry months, and number of rainy days. Mt. Assirik is also
the hottest such site: the coolest mean maximum temperature at Mt.
Assirik exceeds the hottest such temperature at any other site. Mt.
Assirik is the only site where chimpanzees have been studied in which
the majority of vegetation is grassland. Forest constitutes less than 3%
of the surface area. In summary Mt. Assirik presents a truly open savanna
habitat and is thus unique amongst sites where chimpanzees have been
studied. These results are compared with data from a tropical foraging
human society, the !Kung San of southern Africa. The !Kung San's habitat
is drier on most (but not all) criteria, but Mt. Assirik is hotter. The
climate and vegetation of Mt. Assirik strikingly resemble those
reconstructed for the Plio-Pleistocene in eastern Africa. This suggests
that the chimpanzees of Mt. Assirik; provide a useful model for inferring
the processes of adaptation in early hominids.

End quote

Alex Duncan
Dept. of Anthropology
University of Texas at Austin
Austin, TX 78712-1086
512-471-4206
aduncan@mail.utexas.edu