Dr. Donald Prothero of Occidental College will speak on his research on climate change and The La Brea tar pits, one of the most complete fossil records of the last 40,000 years. Geochemistry shows dramatic climate change from sage-oak chaparral to snowy coniferous forests during the glacial peak, then back to chaparral. Dr. Prothero has studied the effects of this change on Dire wolves, saber-toothed cats, Ice Age lions, bison, horses, camels, ground sloths, and birds- with some surprising results. He will also be available to sign his books, "Catastrophes!" and "Evolution".