When seeking a mate, chimpanzees get more selective and choose a partner whose genetic makeup most differs from their own, researchers have found.The study showed that chimps can differentiate between genetically similar mates and more distant ones, even among non-relatives and strangers.Many animals avoid breeding with parents, siblings and other close relatives. But chimpanzees are unusual in that even among non-relatives and virtual strangers they can tell genetically similar mates from more distant ones, said lead author Kara Walker, postdoctoral researcher at Duke University in North Carolina, US.Although, it is not yet discovered as to how exactly they discriminate, but it might be a guess based on appearance, smell or sound, explained Anne Pusey, Professor at Duke University.For the study, the team took DNA samples of 150 adult chimpanzees in Gombe National Park, Tanzania.
The results showed that female chimpanzees who leave their fathers and brothers to establish a new family elsewhere tend to show an even stronger preference for genetically dissimilar mates than do females who remain with their kin throughout adulthood.Inbreeding depression -- when offspring inherit the same harmful version of a gene from both parents and genetic vulnerabilities that are normally masked become active -- may be one of the reasons why chimps distinguish degrees of genetic similarity among unfamiliar mates who are distant from them in their family tree.In addition, female chimps also unconsciously select the sperm of mates who are most genetically distinct, researchers stated, in the study appearing online in the journal Royal Society Open Science.