Donald Redfield Griffin was an American professor of zoology at various universities who conducted seminal research in animal behavior, animal navigation, acoustic orientation and sensory biophysics. In 1938, while an undergraduate at Harvard University, he began studying the navigational method of bats, which he identified as animal echolocation in 1944. In The Question of Animal Awareness (1976), he argued that animals are conscious like humans. Griffin was the originator of the concept of mentophobia: the denial of the consciousness of other animals by scientists.