Sheep can be trained to recognize faces of celebrities, a Cambridge University study found. Given a choice, the sheep picked the familiar celebrity's face over an unfamiliar face the majority of the time, the researchers report November 8 in Royal Society Open Science.
In experiments in which the animals were rewarded with food for picking out portraits of Bruce, Watson and Barack Obama, sheep proved they were experts at identifying individuals. But there are at least eight sheep who can recognize the former president by his face.
In addition to being shown images of the celebrities facing forward, scientists also tested the animals' ability to recognise the faces in photographs taken from other angles.
In fact, they could even recognise people when pictures were altered or were taken from a different angle, an ability only previously recorded in humans and primates.More news: Daylight Savings Time ends November 4
"Sheep are capable of sophisticated decision making", said study author Jenny Morton, a neurobiologist at the University of Cambridge. Morton, who studies Huntington's disease, uses them as a stand-in for humans, in part because "sheep have large brains with humanlike anatomy".
Jake Gyllenhaal, seen here with an animal that is not a sheep.
"Sheep are long-lived and have brains that are similar in size and complexity to those of some monkeys". Seven out of 10 times, the animals would favor the familiar faces of their handlers over the celebrities.
Morton and her colleagues released eight sheep one-by-one into a pen outfitted with two computer screens. "Either the human face is similar enough to the sheep face that [it] activates the sheep face-processing system, or human-face recognition relies on more general-purpose recognition systems". A celebrity's face would appear on one screen, while a different image appeared on the other. "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". Over time, they learn to associate a reward with the celebrity's photograph.