Philosopher of biology Marjorie Grene died March 16th in Blacksburg, Va., at the age of 98. Grene studied the synthetic theory of evolution, the implications of chance in natural selection, and the New York Times says that her "guiding light was Aristotle."

"She was arguably the founding figure in the new field of the philosophy of biology," says Michael Wedin, a philosopher at the University of California, Davis.