Exhibits tracking the natural world since prehistoric time (anthropology to zoology). In the Rotunda, taxidermic African elephant Henry in a replica Angolan habitat. Hall of Geology, Gems and Minerals (Hope Diamond), Ocean Hall, Hall of Human Origins. Butterfly Pavilion ($6.50-$7.50; Tu free with timed tickets). “Q?rius,” 10,000-square-foot learning center for teens. Cafe and gift shop. Daily 10 a.m.-5:30 p.m. Free.