Re: Earliest Hominids

ima pseudonym (fictitious@alias.incognito.myob)
Thu, 29 Jun 1995 10:58:47

In article <3su7qh$bq2@geraldo.cc.utexas.edu> Alex Duncan <aduncan@mail.utexas.edu> writes:
>In article <3sp58o$gib@portal.gmu.edu> HARRY R. ERWIN,
>herwin@osf1.gmu.edu writes:
>>I thought this, too, until I saw Holloway, Early Hominid Endocasts, in
>>Tuttle, where he used a figure of 20 kg for A. africanus. His arguments
>>make sense, too. It's a question of how much flesh you put on those bones,
>>and 28-30 kg corresponds to a moderate degree of robustness, while 20 kg

>I'm unfamiliar w/ this particular Holloway reference. More details?
>Estimating body weight is problematic. I find it encouraging, however,
>that regression equations using EITHER human or ape (or combination)
>derivations for either articular surface dimensions or diaphyseal
>dimensions seem to agree on around 28 - 30 kg for AL 288, and for Sts 14.

>I agree that as we go back further, we might expect to see hominids
>getting smaller and smaller. I suspect A. ramidus will turn out to be
>smaller than the other Australopithecines, and that our common ancestor
>w/ chimps may have weighed 10 - 15 kg.

Wow! That small? In that case, besides the crocodiles and leopards,
our ancestors might well have had to watch out for the immediate ancestors
of _Python sebae_. Lots of different medium-sized-to-large carnivorous
animals may have been potential hominid predators back then.

When looking at pet store or zoo animals of various sorts I sometimes
muse to myself : "I wonder when was the last time that a direct ancestor of
_yours_ ate a direct ancestor of _mine_?" Apparently it may often have
been more recent than I supposed...

a fun thought