> A curious aspect of this debate is the fact that mega fauna did survive
and
> thrive in Africa  ( the challenges of this century aside).  Why?

The same things protected the tropical fauna that protected them until this
century, tropical diseases.  Until recently with the development of DDT and
other insecticides diseases such as sleeping sickness, malaria etc. that
have  little or no effect on tropical primates prevented humans and their
temperate domestic animals from thriving in tropical Africa.  Africa's
temperate mega-fauna was wiped out along with other old world megafauna when
Man domesticated the dog and the climate began to warm forcing the megafauna
to migrate to the arctic.  Although previous warm periods during the
Pleistocene were warmer and longer than the one we now inhabit the temperate
megafauna survived.  Mathematical modeling has shown how the new
super-predator Man-Dog packs could have easily caused extinction under such
circumstances.  The last known herds of megafauna survived in the Old World
( Wrangle Island )  safe from Man until about 4,000 BC.

Ray Audette
Author "NeanderThin"
http://www.NeanderThin