Charles Darwin's legacy February 24 marks the 150th anniversary of the publication of Charles Darwin's "The Descent of Man, and Selection in Relation to Sex." His influential work lives on today in advances in the field of evolutionary biology. Trip of a lifetime At the age of 22, Charles Darwin sailed around the world on the HMS Beagle, happening upon new landscapes, cultures and, of course, animals. During his travels, he developed his scientific theory of evolution. Fossils in particular raised questions for the young Darwin. As he examined the bones of large, extinct mammals and fossilized trees, he thought about deep time.