Did gassy dinosaurs help contribute to global warming?

WASHINGTON (AP) — Potty humor just got prehistoric. A new study suggests that dinosaurs may have helped keep an already overheated world warmer with their flatulence and burps 200 million years ago.

The research published Monday in Current Biology suggests that large dinosaurs made a significant contribution to the greenhouse effect back then.

Study author David Wilkinson of Liverpool John Moores University in England estimated that about 570 million tons of methane came from dinosaurs. That's similar to atmospheric levels of methane today produced by livestock, farming and industry.

Wilkinson said dinosaur gas was just one factor at a time when the world was quite tropical.

Outside climate experts say the study makes some sense, but that the warming from dinosaur gas back then is dwarfed by man-made carbon dioxide today from industry.