Geologic evidence piles

up that humans are the culprits in mass

extinctions on two continents — “For decades, scientists have debated what caused the mass

extinctions. Some saw humans as the guilty party; others blamed

climate change. Without solid evidence, the debate was a draw.

But two recent studies are tipping the balance in favor of humans as

the culprit. Though not a smoking gun, the new research places man at

the scene of the crime and casts serious doubt on his alibi.” The Dallas Morning News