Geoffroy Saint-Hilaire, Isidore (1805-1861)

French zoologist and anatomist who specialized in the study of apes and developed a system for their classification. He also studied the manner in which animals interact with their environments.

The only son of Etienne Geoffroy Saint-Hilaire, Isidore was born in Paris and, though he wanted to study mathematics, ended up working for his father in his laboratory. At the age of 25, he delivered a series of lectures at the Athénée 1837, and was appointed professor of comparative anatomy at the Faculté des Sciences, and then professor at the Museum d'Histoire Naturelle, replacing his father in both positions.

From 1844 until 1850 he was the inspector general of education before becoming the professor of zoology at the Sorbonne. His research included a system for the classification of the apes, and he identified many of their infantile characteristics. In 1856 he led a campaign to encourage the French public to eat more horse meat. In 1859 he wrote a history of the origin of species which put Darwin's proposals in the context of his French predecessors, including Buffon, Lamarck and Etienne Geoffroy Saint-Hilaire.