The Galapagos penguin a study of adaptations for a life in an unpredictable environment
Thesis (Ph. D.)–Ohio State University, 1974. Includes bibliographical references.
The Ecology of Color Vision
Colour vision in man is well understood, but for obvious experimental reasons it is less so in the case of other animals. Some evidentally have a three-colour system similar to our own but based on different primary colours. In particular, some are sensitive to ultraviolet light, which the human eye is not.