Many animals, including humans, avoid mating with close relatives. Yet it’s not always clear how they distinguish kin from nonrelatives. A study published last month (February 24) in Current Biology finds that death, dispersals, and an unknown innate strategy help wild baboons avoid inbreeding. But the animals do sometimes mate with relatives, and this is more likely to happen with paternal than maternal kin.
Inbreeding is a problem in general “because every organism harbors some bad genetic bits that remain recessive,” says coauthor Susan Alberts, an evolutionary anthropologist at Duke University. “However, mating with relatives can bring such [deleterious genetic variants] together,” which is bad news for offspring. To avoid inbreeding, maturing primates tend to leave their original social groups to find mates in other groups. In wild baboons (Papio cynocephalus), for example, adult males frequently leave the natal troop while females stay, ensuring that siblings from the same mother ...
