‘Paradise Lost–The Late Ordovician of New York’ at Thacher Nature Center. This talk focuses on trilobite diversity in the Late Ordovician of New York in comparison with other parts of Laurentia (North America) and examines the environmental changes in our area that affected the organisms that lived here. 2 p.m. at 87 Stan Levine Dr, Voorheesville, 12186. Call 518-872-0800 for more info.