Re: Who Killed the Australopithecines?

Dave Oldridge (
18 Apr 1995 10:29:53 -0300

In article <>, (BARD) wrote:
> In article <>,
> Dave Oldridge <> wrote:
> >In article <>,
> >rtravsky@UWYO.EDU (Rich Travsky) wrote:
> >
> >> (BARD) writes:
> >> >
> >> > Everything being equal, they were better equipped to survive
> >> > than either ape or man; yet they perished... How and by whom?
> >> >
> >> >
> >> > Bard
> >> Myself, I suspect evolution...
> >
> >I've been following this thread for a bit. It seems to me that there's
> >a misconception at the root of it. It is *not* necessary for a species
> >to be "killed off" in order for it to become extinct. Introduce a
> >competitor with a mere 1% reproductive advantage into the same range and
> >it will happen due to normal attrition due to disease, predation, etc.
> >
> >Even a very elementary computer simulation will serve to demonstrate
> >this. However, if you remove the normal constraints on population
> >growth, then both may survive for a very long time.
> >
> > --
> > Dave Oldridge
> >
> ______________________________________________________
> I'm not certain we have any reason to believe H. habilis,
> might have been more productive than earlier hominids;
> in fact, aren't lower species as a rule more productive than those
> that follow (shorter gestation, more multiple births, etc.)?
> I'd give the reproductive advantage to A. species.

I thing you misunderstand what is meant by a reproductive advantage. It
is not a simple question of who produces more offspring (although, all
other things being equal, it can come down to that). It's more a
question of how many of those offspring survive to reproduce further.
Dead ends don't count. But any combination of factors that produces a
1% edge will accomplish the result by natural attrition, ASSUMING the
population has saturated its range (which can happen with a pretty
sparse population of resource-hungry hominids).

> The point here is that genocide seems the only logical explanation
> to the extinction of A. species by H. habilis, H. habilis by H.
> erectus, H. erectus by H. sapiens.

I doubt it. And there's no real reason to assume it. Sure, some
individuals of earlier species were undoubtedly killed by members of
later species. That process continues to this day, but we rarely kill
chimps and gorillas out of any sense of revulsion or any desire to
commit genocide. More likely, the habitats just continued to change,
giving the newer hominids an ever greater advantage, while the pongids
continued to thrive in THEIR habitats.

And it happened over far too long a period for it to be genocide.

Dave Oldridge