The Atlanta Journal-Constitution
Sheep recognize photos of Obama
Animals show high levels of cognitive functions in study.
sheep billion Of the on have roughly Earth, no roughly idea 1.1 billion who 1.1 Barack Obama is. But there are at least eight sheep who can recognize the former president by his face. After a few days of training at the University of Cambridge in England, the animals learned to select the former president’s portrait out of a collection of photos.
Recognizing Obama meant the sheep won a snack. The scientists, in turn, were rewarded with better ways to measure sheep brain func- tion.
Sheep are about as capable of recognizing faces as mon- keys or humans, University of Cambridge researchers report Tuesday in the jour- nal Royal Society Open Science. The Cambridge flock, eight female Welsh Mountain sheep, successfully learned the faces of four celebrities in a recent experiment: Obama, British newscaster Fiona Bruce and actors Emma Watson and Jake Gyllenhaal.
“Sheep are capable of sophisticated decision mak- ing,” said study author Jenny Morton, a neurobiologist at the University of Cambridge. Seven years ago, she said, she bought these sheep out of the back of a truck on its way to a slaughterhouse. Morton, who studies Huntington’s disease, uses them as a stand-in for humans, in part because “sheep have large brains with humanlike anatomy.”
The woolly critters learned to recognize human celeb- rities 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 celeb- rity 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. “I’m sure it will surprise other people, but to me this is all well known,” said Jonathan Peirce, who studies visual systems at the Univer- sity of Nottingham in Britain. Peirce, who was not involved with this work, said this study is similar to work he and his colleagues conducted in 2001. “My 2001 paper looked very carefully at this with a wider range of stimuli, more sheep and more conditions,” he said. “I guess they have extended our work to show that sheep generalize viewpoints of the faces, which does require a rich representation of the identity.” During the training period at the University of Cambridge, the animals learned to recognize celebrities in forward-facing photos. In follow-up experiments, the authors of the new study had the sheep once again chose between images of celebrities or strangers. In these trials, though, the celebrity’s heads were tilted, beagle-like, at unfamiliar angles. They also wore different hairstyles. The sheep were less successful at identifying the tilted celebrities but still performed better than chance. Their success rate decreased by 15 percent. This was on par with research in humans - 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, the authors noted.