Thursday, April 24, 2008

Megafauna update Did a Significant Cool Spell Mark the Demise of Megafauna?
The end of the Pleistocene Epoch was marked with steadily warmer temperatures and the great ice age glaciers that covered vast areas of North America were in retreat.

Except for a 1,000-year period when things once again suddenly got remarkably colder, the cause of which is a mystery that researchers of the period have argued over for years.

Geologically, the start of this period is marked by a “black mat” of organically rich soil. Below the mat is the evidence of late Pleistocene flora and fauna, including the very large animals that once roamed across North America: mammoth and mastodons, dire wolves, horses, short-faced bears and others.

Hmmm. Gonna have to read that. There will be questions on the exact timing of various extinctions.