New research out of Purdue University finds that a global warming event called the PETM made parts of the tropics too hot for living organisms to survive. And though the PETM happened many millions of years ago, these new scientific revelations are pertinent to the present day. The reason is that human activity in the form of fossil fuel burning is now rapidly causing the globe to heat up. And such warming, if it continues, could well turn large sections of the tropics into a dead zone.

PETM — Warm-up Sparks Global Upheaval, Extinction

The PETM was a big global warm up that happened 56 million years ago as the Paleocene epoch passed into the Eocene. It is numbered as one of many hothouse extinctions occurring in the geological record. And it is generally thought to have been one of the milder such events — especially when compared…