Re: Hominid Family Tree

Debra Mckay (debra.mckay@utoronto.ca)
Fri, 13 Oct 1995 14:40:48 GMT

>
>How about some specifics? How is H. rudolfensis derived postcranially?
>What specimens are you including in H. rudolfensis?
>
>I'm not denying what you say -- It's my impression that H. rudolfensis
>has H. erectus-like postcrania, but that impression is based on pretty
>scrappy material that could turn out to belong to H. erectus if it gets
>older than 1.77 Mya.

You're right--the evidence is scrappy, but the following has been
assigned to the H. rudolfensis hypodigm (by Wood, 1992):

KNM ER 813: right talus and distal right tibia (fragmentary)
" " 1472: relatively complete right femur
" " 1481: left femur, both ends of left tibia, distal end left fibula

I've seen KNM ER 3228 (right innominate) attributed to H. rudolfensis as
well, but I think there's less support for it.

They could turn out to be H. erectus/ergaster, as you say--but I also
understand that they were asigned to that taxon based on traits that are
diagnostic of Homo in general.

What I'm not sure of is how much all this dispute is due to the fact that
workers were just plain discomfited by the very short time span indicated
between the primitive OH 62 condition and the practically
modern--morphologically adapted to climate and all--KNM WT 15000;
somewhat less than 200,000 years, I think, if H. habilis gave rise to H.
erectus/ergaster. H. rudolfensis seems to give a bit of breathing room,
if postcranially it is more derived, and yet older. I'm not saying that
this justifies attributing anything to anything; it's just a matter of
interest.

Anyway, this is what makes the whole field of paleoanthropology so much
fun--tomorrow everything could change again!

Thanks,

Deb.