Re: Hominoid split and other questions

Jim Foley (jimf@vangelis.FtCollins.NCR.com)
14 Nov 1995 19:52:44 GMT

In article <garry-1011951720190001@archmac-202.arch.su.edu.au>,
Garry Stevens <garry@arch.su.edu.au> wrote:

>* What is the most recent known/suspected common ancestor to living apes
>and the hominids? Haven't been able to get a straight answer from the
>various pieces I've read.

Not sure, I havent read up on these older fossils. Maybe stuff like
Kenyapithecus, or Proconsul, would be a candidate??

>* People sometimes talk about several significant gaps in the
>hominid/homonoid fossil record. What are the time-periods for these? Is
>one of these gaps right where we would expect to find the hominoid/hominid
>ancestor?

There's precious little in the few million years preceding 4.5 (used to
be 4.0 until recently) million years, which is where we would expect to
find the most recent common ancestor. Fossil evidence in the 2.5 to 2.0
million range is also pretty scanty.

>* Mr Foley mentions that previously the ape-hominid split was taken as 15+
>Mya, perhaps up to 30+ Mya. Biochem evidence revises this to 5-10 Mya. I
>presume the prior estimates were derived purely from fossil evidence. If
>the genetic dating evidence is now widely accepted, how could the physical
>anthropologists have been so out of whack?

I think the physical evidence was always fairly limited. There were a
few jaw fragments from Ramapithecus that used to be cited as evidence,
for example. Part of it may have been a bias against the idea that we
were closely related to the living apes. Roger Lewin's book "Bones of
Contention" would probably be a good source on this.

>Apologies for the simplistic nature of these queries. The tedious AAT
>discussions here seem to have drowned much more interesting and important
>questions.

Yes indeed.

--
Jim (Chris) Foley, jim.foley@symbios.com
Assoc. Prof. of Omphalic Envy Research interest:
Department of Anthropology Primitive hominids
University of Ediacara (Australopithecus creationistii)