It’s an unlikely animal to exhibit this talent—but scientists just discovered that sheep are about as capable of recognizing faces as monkeys or humans.
University of Cambridge researchers reported yesterday in the journal Royal Society Open Science that they’d trained eight female Welsh Mountain sheep to recognize the faces of four celebrities: Barack Obama, British newscaster Fiona Bruce, and actors Emma Watson and Jake Gyllenhaal.
To the sheep, there’s nothing special about these faces—they just know what they look like now, and can spot them on command. The sheep picked out the correct face eight out of 10 times, on average.
Here’s Ben Guarino, reporting for The Washington Post:
The woolly critters learned to recognize human celebrities through three training scenarios. In each step, the sheep were presented with two options: a photo of the celebrity facing forward for the camera, or a photo of something else. The farm animals had 15 seconds to approach the celebrity image and trigger an infrared sensor. If the sheep chose correctly, the testing device popped out a treat.
The first test was the simplest. The sheep chose between a black screen or the celebrity face. The second round was slightly more challenging. Celebrity profile photos were randomly paired with images of one of 62 objects, all head-sized but lacking faces. (A sheep might have had to select Emma Watson vs. a football helmet or gas lamp, for instance.) The third test pitted the sheep’s celebrity targets against unfamiliar humans.
“We chose the celebrities almost randomly,” Morton said, as long as there were lots photos to choose from. “I wanted people that the sheep had not met (I am very sure of this).”
Sheep, on average, chose the celebrity faces correctly in 8 out of 10 trials. That’s significantly better than the 50 percent rate the sheep would have shown if they were guessing haphazardly, the authors of the study pointed out.
What’s different about this experiment compared to previous experiments is that this group of researchers has shown that sheep can recognize faces even when they’re tilted at various different angles. It suggests that sheep have a more nuanced, abstract understanding of facial structure than once thought. Even though sheep’s aptitude decreased for the tilted images, the amount of decline is actually similar to the equivalent decline between humans’ ability to recognize frontward versus tilted faces.
If Jenny Morton, a neurobiologist at the University of Cambridge, hadn’t bought these eight sheep seven years ago from a truck on its way to a slaughterhouse, the small flock would likely be dead. But now, they’re guinea pigs for Huntington’s disease research. Morton says that the finding shows that facial recognition is a complex brain process—and that sheep, which have large brains with a structure similar to humans’, could help elucidate the process.
The research is important not just for Huntington’s disease (which involves loss of facial recognition capabilities), but other conditions and disorders in which face identification is more difficult. And of course, the more we learn about facial recognition, the better we can develop surveillance technologies that can keep us safe.