Re: An alternative to ST and AAT
Phil Nicholls (pnich@digiworldinc.com)
Sat, 19 Oct 1996 23:20:31 GMT
Newington Reference Library <fp96@dial.pipex.com> wrote:
>A NEW APPROACH TO THE PROBLEM OF HUMAN EVOLUTION
>
>by Andrew Lewis
>
>The Savanna Theory (ST) and the Aquatic Ape Theory (AAT) both make
>certain assumptions that need to be challenged.
The "savanna theory" is a straw man constructed by advocates of the
aquatic ape "theory".
>Both believe that our remote ancestors stopped living in one environment
>(the forest) and started living in another (either the savanna or the
>coastline).
Sorry, but the archaeological and paleontological data strongly
supports the inference tha (a) early hominind accestors were initally
arboreal and (2) hominids moved out onto the savanna. This is not a
theory. Theory is "why they moved onto the savanna." Those who
advocate the AA"T" advocate only an additional stop along the way
that is NOT supported by any archaeological or paleontological data.
>Another possibility is that our ancestors evolved to become more
>adaptable, to be able to exploit different environments seasonally. They
>could have moved between at least three different environments to exploit
>the seasonl abundance of each.
I would say that most anthropologists today maintain that early
hominids exploited a variety of resources. Seasonality, however, has
a much different meaning in equatorial Africa.
>When the East African forest diminished, it did not do so evenly. In the
>river valleys the forest remained. Where the river approached the sea,
>the valley became wider and such features as delta formation, meandering
>and braiding allowed for the forest to become more extensive.
River deltas are mostly grassy wetlands and not forests.
>I can imagine our ape ancestors becoming concentrated in these valleys,
>especially closer to the sea. Each valley would eventually have become
>an 'island' separated by expanses of grassland. The forest would have
>continued to provide food for the apes, but only at certain times of the
>year. It would have become more seasonl compared to the rain forest that
>still exists in West Africa. At other times of teh year, the apes would
>have gone hungry.
I think the word you are looking for is Gallery Forests. Why would
these forests have provided food only at certain times? In East
Africa you have rainy season and dry season variation but gallery
forests are stable year round.
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