Baer, Karl Ernst von, bair, kahrl urnst fuhn (1792-1876), a German biologist, is considered the founder of embryology. Embryology is the study of the early development of animals and plants. Baer identified the primary cell layers of embryos of mammals, and he was the first to discover the egg of the mammal in the ovary. Baer's writings include The Origin of Mammal Eggs (1827) and The Embryology of Animals (1828, 1837).