Whenever the world's tropical seas warm several degrees, Earth has experienced mass extinctions over millions of years, according to a first-of-its-kind statistical study of fossil records. And scientists fear it may be about to happen again — but in a matter of several decades, not tens of millions of years. Four of the five major extinctions over 520 million years of Earth history have been linked to warmer tropical seas, something that indicates a warmer world overall, according to the new study published Wednesday. http://news.yahoo.com/s/ap/20071024...s&printer=1;_ylt=Akyb.vZIRqZI_UrtFIMiDJRxieAA WOW we had global warming over 500 million years ago. I guess this pops Gores bubble:laugh: .