Colgate's celebration of the 200th anniversary of Charles Darwin's birth kicked off Tuesday with a lecture about one of the naturalist's legacies - the study of biodiversity - and a warning that the home for a vast array of plant and animal species is threatened.

The university has several events this week to honor Darwin, including the dedication of a "thinking path" at the top of the former ski hill, a Tree of Life cake baked by students, a film, and a colloquium.

On Tuesday, students filled Meyerhoff Auditorium in the Ho Science Center to listen to Catherine Cardelús, assistant professor of biology, discuss "Darwin, Plants and Tropical Diversity."

Geology professor Connie Soja and 13 students in her Core Distinction course recently had a "wonderful conversation" with the great-great grandson of Charles Darwin, even though some 3,444 miles separated the participants.

Soja's students could see and interact with Randal Keynes, who spoke to them via a software program called Skype and whose image was projected on a screen in 209 McGregory, a room specially outfitted to handle video conferences.