On the western side of the Winnemucca Lake Basin in northwest Nevada is a carbonate tufa mound which contains the oldest petroglyphs (picture-writing) in North America. This mound of volcanic rock represents a monumental find to give us more understanding of this era (up to 14,800 - 13,200 years ago) of prehistory. Professor Benson will present an overview of this find and of the research behind the dating of the petroglyphs. Thursday | Feb. 27 | 7 p.m. | CU Museum of Natural Hist. Paleontology Hall | Free