Re: Alex's gibbon-like CA

Paul Crowley (
Thu, 09 Nov 95 00:23:23 GMT

In article <47q84c$> "Alex Duncan" writes:

> There is nothing about anything I've written that suggests I think that
> the environment changed and an ENTIRE SPECIES made the transition to
> part-time terrestrial bipedalism necessitated by the change in habitat.

I did not suggest that this was your error. You made the classic
"evolution forces" error - one that is so universal in PA literature
that you hardly notice it after a bit. (It's also a big weakness of
the standard AAT, although that's *never* pointed out.) It states
that a major environmental change will force a change of habit in
a species and then *some* members - those that are best adapted to
the new conditions will cross over into a new species. It rarely
brings up the issue of the necessary isolation.

You claim that your original posting was about isolation!

> Conditions during the terminal Miocene were ideal for the isolation of
> small subpopulations of once-widespread taxa.

Pull the other one, Alex. You boobed. If you had meant "isolation"
you would have said "isolation". I go on about my "cute little
'evolution forces' idea" because it's an appalling error, it's
appallingly common, and people who should know better (like your
own good self) make it all the time.