UC’s year-long celebration of the 200th anniversary of the birth of Charles Darwin and the 150th anniversary of “On the Origin of Species” presents John van Wyhe, founder of Darwin Online. He will discuss “Mind the Gap: Did Darwin Avoid Publishing His Theory for 20 Years?” April 16, 4 p.m., Engineering Research Center, Room 427. On April 17, 4 p.m., he will discuss “Charles Darwin: The True Story” at the Public Library’s Huenefeld Tower Room (800 Vine Street, 3rd Floor). More information is online.