In 1926, a Russian Biologist Tried to Create a Human-Chimpanzee Hybrid

In the mid-1920s, amid fierce public debate over Darwin's theory of evolution -- the same debate behind the 1925 prosecution of Tennessee teacher John Thomas Scopes for teaching that humans descended from other species -- Russian biologist Ilya Ivanov set out to crossbreed humans and chimpanzees. Ivanov, who had developed methods for artificially inseminating domestic animals, argued that a successful 'humanzee,' created through interspecific hybridization, would demonstrate biological continuity between the two species. Historians have proposed motives including anti-religious Soviet propaganda or Soviet utopian ambitions; Ivanov's own motivations remain uncertain.

According to research by science historian Alexander Etkind of Central European University, Ivanov traveled with his son to French Guinea, now Guinea, in 1926, captured several live adult chimpanzees, and inseminated female chimpanzees with human sperm. He also sought to inseminate local women with ape sperm without their consent, under the guise of medical examinations at a community hospital, but French colonial authorities blocked the plan.

None of Ivanov's experiments succeeded. He returned to the Soviet Union with 20 chimpanzees, only four of which survived the journey, and set up a primate facility near the Black Sea. Soviet officials authorized him to recruit consenting women for insemination with ape sperm, but by the time he had identified volunteers, only one ape remained -- an orangutan -- and the experiment never proceeded. In 1930, Ivanov was arrested and exiled on unrelated political charges, ending his hybridization attempts.

James Mallet, a Harvard University evolutionary biologist who studies interspecific hybridization, called Ivanov's experiments 'a horrible thing to do' and said a human-chimpanzee hybrid is theoretically possible but highly unlikely, given roughly 6 million years of evolutionary divergence between the species. Hybridization is more common in nature than widely believed, Mallet noted, occurring in roughly 10% of animal species and 25% of plant species -- and Neanderthals are known to have interbred with Homo sapiens tens of thousands of years ago, leaving many people alive today with a small amount of Neanderthal DNA.