1792-1876

Estonian Biologist

Karl Ernst von Baer was an Estonian biologist who discovered the mammalian ovum—the reproductive egg in female mammals. He made significant contributions to the study of the embryonic development of animals.

Born in Piep, Estonia, to parents descended from Prussian nobility, Baer studied medicine at the University of Dorpat in Estonia. He continued his studies in Vienna, Austria, and later in Würzburg, Germany. He then accepted a position to teach anatomy, anthropology, and zoology at the University of Königsberg.

From his investigations at Königsberg arose one of Baer's most important discoveries. Scientists had long been trying to determine the nature and location of the mammalian egg. In 1672 Reinier de Graaf (1641-1673) discovered follicles in the ovaries and believed that the follicles themselves might be eggs. When he found structures in the uterus that were even...