Mountain gorilla inbreeding has distorted their facial features

The degree of facial feature distortion is on the rise in certain endangered gorilla species, along with their level of inbreeding. Facial asymmetry in primates – including humans – is marked by a sort of spiraling of the facial features around a central point just above the jaw. Once thought to be a consequence of early life challenges, a new study in gorillas suggests that the phenomenon may result from inbreeding, says Kate McGrath at the University of Bordeaux, in France. "It's either that inbreeding is somehow directly affecting their facial development, or that [being] inbred is making them more susceptible to … illness or other things that pop up in early life," she says. Or it may be a combination of both factors, she adds.