Re: An alternative to ST and AAT
Paul Crowley (Paul@crowleyp.demon.co.uk)
Thu, 21 Nov 96 22:00:46 GMT
In article <01bbd6ce$eca71300$1b2470c2@default>
jdwaters@dircon.co.uk "John Waters" writes:
> Gerrit Hanenburg <G.Hanenburg@inter.nl.net> wrote in
> article <56p69i$6uh@news.NL.net>...
> > >the life expectancy of the australopithecines?
> >
> > 42.2 years.
> > Calculated using the regression equation for primates from
> > Harvey and Clutton-Brock (1985),
> >
> > log (lifespan)=log (780.9)+0.29*log (female bodyweight)
> > (lifespan in days,female bodyweight in grams)
> >
> > Female bodyweight A.afarensis= 29.3kg. (McHenry,1992)
1) Is a regression equation for primates appropriate for
hominoids? I'd expect that one using gibbons, chimps, gorillas
and orangs would give a better (and larger) figure.
2) Female australopithecines are particularly small for
hominoids; (especially for a terrestrial hominoid;) I suggest
that when they adapted to their niche probably they experienced
a reduction in size; that this was unlikely to have affected
their longevity and that the figure should therefore be larger
for this reason as well.
> JW: Phew. Just as well I didn't forward my information to
> Roh. In the well known *science* journal National
> Geographic Vol 168, No. 5 (1985), it is reported that an
> exhaustive investigation by Alan Mann of the University of
> Pennsylvania indicated an average life span for A.
> africanus of 22 years.This was based upon a study of teeth.
A.africanus fossils are found well inland, a long way from
their natural home on the littoral. Such individuals would
have been young adults expelled, or wandering away, from their
natural home and living on an unaccustomed diet. Their teeth
would have suffered an excessive degree of wear, almost
certainly being a cause of their early death. A study of
the teeth of A.afarensis on sites near to Afar will yield
different results. (A prediction, btw).
Paul.
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