The Columbia Encyclopedia, Sixth Edition. 2001-07.
Geoffroy Saint-Hilaire, Étienne
(tyn´ zhôfrwä´ sNtlr´) (KEY) , 17721844, French zoologist. He was professor at the Museum of Natural History (17931840) and also at the Faculty of Sciences (from 1809), both in Paris, and was a member (17981801) of Napoleons scientific staff in Egypt. He expressed in his Philosophie anatomique (2 vol., 181822) and in other works the theory that all animals conform to a single plan of structure. This attracted many supporters but was strongly opposed by Cuvier, who had been his friend, and in 1830 a widely publicized debate between the two took place. Some of Geoffrey Saint-Hilaires ideas have been confirmed by modern developmental biologists. His son, Isidore Geoffroy Saint-Hilaire, 180561, also a zoologist, was an authority on deviation from normal structure. He succeeded to his fathers professorships.