Themed “Seeking the Unknown: Perspectives on Louisiana’s Natural History," scholars from Louisiana and abroad discuss the state’s natural history at the annual symposium. Registration includes an event previewing the symposium's companion exhibition at the Historic New Orleans Collection (533 Royal St.) 6 p.m. to 8 p.m. Feb. 22. Visit www.hnoc.org/programs/symposia.html for details. Admission $85. 8:30 a.m. to 4 p.m.