A recently published study finds that sheep can recognize human faces from photographs on computer screens.
Many other animals are known to recognise the faces among their own species, while some - including macaques, horses, dogs, mockingbirds, and sheep - can identify individuals from other species too. They were able to identify the faces of celebrities at different angles (although there was a decrease in performance of about 15%), demonstrating that they are not stupid.
A sheep "model" of Huntington's disease has been bred, displaying similar brain and social changes as witnessed in human patients. Morton, who studies Huntington's disease, uses them as a stand-in for humans, in part because "sheep have large brains with humanlike anatomy". When a portrait of the handler was interspersed randomly, the sheep chose them seven out of 10 times. A celebrity's face would appear on one screen, while a different image appeared on the other.
The woolly creatures could reliably pick out their human handlers without any previous photographic training at all, showing they can spot a familiar face.
The sheep's accuracy dipped to about 66 percent - "a magnitude similar to that seen when humans perform this task", the team reported in the journal Royal Society Open Science. 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.
In a separate test, researchers wanted to see if the sheep would recognize human trainers they already know without any training like they underwent in the pen with the celebrity faces. Maybe they just didn't like that the non-familiar lacked a reward, for example. In these initial tests, the sheep were shown the faces from the front, but to test how well they recognised the faces, the researchers next showed them the faces at an angle.