Though they have never seen Harry Potter, at least eight sheep in England are now able to recognize Emma Watson.
As Ian Sample reports for the Guardian, neuroscientists at Cambridge University have found that after a few days of training, Welsh Mountain sheep learned to distinguish the famous countenances of four celebrities—Watson, Jake Gyllenhaal, Barack Obama and the television presenter Fiona Bruce—with an accuracy that rivals humans’ facial recognition abilities.
Previous studies have shown that sheep are adept at recognizing their handlers and other members of their flock. The new research suggests that sheep can also learn to identify humans that they have never seen before.
With the help of a specially designed pen, researchers presented the sheep with two different screens. During the first round of testing, one screen was blank, while the other displayed one of the four celebrities’ photos. If the animal approached the celebrity picture within 15 seconds, an infrared sensor was triggered and the testing device would release a treat. If the animals approached the blank screen, a buzzer would sound and they would not receive any tasty snacks.
In the next phase, according to Ben Guarino of the Washington Post, the celebrities’ images were paired with pictures of inanimate and roughly head-sized objects, like a football helmet or gas lamp. The last phase, which was the most difficult, prompted the sheep to choose between the celebrities’ faces and images of people they had never seen before.
The results of the study, published in Royal Society Open Science, showed that the sheep chose familiar images of celebrities during eight out of ten trials, on average—a significantly higher success rate than would be expected if the animals were simply selecting images at random.
“Anyone who has spent time working with sheep will know that they are intelligent, individual animals,” says study leader Professor Jenny Morton in a University of Cambridge statement. "We’ve shown with our study that sheep have advanced face-recognition abilities, comparable with those of humans and monkeys."
In the initial rounds of testing, the sheep were shown images of front-facing humans. During subsequent trials, researchers presented the animals with images of the same celebrities, but this time with their heads titled. The sheep’s ability to correctly select the celebrities dipped by about 15 percent, but that decrease is in line with humans studies, Guarino notes. "One study in 2000 found that the human ability to recognize unfamiliar faces decreases from 90 percent for frontward faces to about 76 percent when faces are tilted," he reports.
Researchers also found that sheep were able to recognize photos of their handlers without any training. “We can’t say for sure that the sheep understand that the pictures represent humans,” Morton told Guarino. “But the evidence is compelling. And there is no reason to think that they would recognize other animals but not humans.”
In addition to being really cool, the results of the study suggest that sheep can be “useful models to help us understand disorders of the brain,” as the Cambridge press release puts it. In fact, when she isn’t training sheep to get familiar with Barack Obama, Morton studies Huntington’s disease, an incurable neurodegenerative condition. She and her team have started studying sheep that have been genetically modified to carry the Huntington’s mutation. And because sheep have large and complex brains that are similar in anatomy to that of humans, the fluffy animals may help researchers better understand this devastating disorder.