Individuals use a variety of cues to identify their own kin and humans can also detect resemblances in families other than their own, in defiance of 'you all look alike to us' jokes.   A new study says that our success in doing so is the same even if those families are not the same race as ourselves. 

In the recent Journal of Vision study, French and Senegalese participants were asked to match photos of parents with photos of children. Both groups were able to detect kinship with the same rate of success, whether they were looking at French parents and children or Senegalese parents and children. The amount of exposure — i.e., how much or how little contact participants had with members of the other race — had no affect on the participants' ability to correctly match parents with their children. 

The researchers from France's University of Montpelier, Japan's Nagoya Institute of Technology and Okinawa University explain that "the importance of exposure for recognizing faces is … supported by a large number of studies showing an "other-race effect," which is defined as a greater capacity to recognize faces of one's own cultural group as compared to faces from other cultural groups."

Lead investigator Alexandra Alvergne said, "Our results suggest that exposure has a limited role in the ability to process facial resemblance in others, which contrasts with the way our brains process facial recognition." Her team concluded that facial recognition and the detection of facial resemblance are probably not processed in the same way.

The researchers believe their findings will be instrumental in other studies. "Brain-imagery studies could investigate whether processing facial resemblance among others is a by-product of the processing of facial resemblance to oneself. It would also be very interesting to explore whether other close-related species share this ability and whether it is linked to any reproductive benefit," Alvergne said.