Chimps and bonobos interbred and exchanged genes
Humans are not the only great apes to have had an ancient fling with related species. New evidence shows that chimps carry genes from bonobos
Chimpanzees and their relatives bonobos are closer than we thought. Bonobos seem to have donated genes to chimps at least twice in the roughly two million years since they last shared an ancestor.
The two closely related apes have occasionally interbred in captivity, and bonobos are renowned for their free and easy sex life. But the finding that they interbred in the wild was unexpected.
The two species split sometime between 1.5 and 2.1 million years ago, around the same time that the Congo River system formed. Wild bonobo populations are entirely contained in that river system, separated from two nearby subspecies of chimps, the eastern and central subspecies.
Scientists assumed the river was an impenetrable barrier, says Christina Hvilsom from Copenhagen Zoo in Denmark, one of the researchers who worked on the genetic project. But it turns out that it must have been breached more than once – although it’s not clear how that happened.