Sheep can recognise Barack Obama's face, University of Cambridge researchers prove
They also picked out Fiona Bruce, Emma Watson and Jake Gyllenhaal - and did a 'double take' when they saw their own handler.
It sounds like the most unlikely of experiments.
But University of Cambridge researchers have proven that sheep can be trained to recognise human faces from photographic portraits.
The scientists at the Department of Physiology, Development and Neuroscience taught eight sheep to recognise the faces of four celebrities - Barack Obama, Fiona Bruce, Emma Watson and Jake Gyllenhaal - from photos displayed on computer screens.
The training involved the sheep making decisions as they moved around a specially-designed pen. At one end of the pen, they saw two photographs displayed on two screens and would receive a food reward for choosing the photograph of the celebrity by breaking an infrared beam near the screen.
If they chose the wrong photograph, the animals were meet with the sound of a buzzer - and received no reward. They learned to associate the reward with the celebrity’s photograph.
Following this training, the intrepid sheep were shown two photograph – the celebrity’s face and another face. The sheep correctly chose the celebrity face they had learned eight times out of 10.
Quite what they would have done if they’d have been confronted with the face of the current US president remains open to speculation.
The purpose of all this is revealed in a study published today in the journal Royal Society: Open Science. It was part a series of tests given to the sheep to monitor their cognitive abilities. As they have relatively large brains and live for a long time, sheep are a good animal model for studying neurodegenerative disorders such as Huntington’s disease.
Professor Jenny Morton, who led the study, said: “Anyone who has spent time working with sheep will know that they are intelligent, individual animals who are able to recognise their handlers.
“We’ve shown with our study that sheep have advanced face-recognition abilities, comparable with those of humans and monkeys.
“Sheep are long-lived and have brains that are similar in size and complexity to those of some monkeys. That means they can be useful models to help us understand disorders of the brain, such as Huntington’s disease, that develop over a long time and affect cognitive abilities.
“Our study gives us another way to monitor how these abilities change, particularly in sheep who carry the gene mutation that causes Huntington’s disease.”
Recognising faces is, of course, an important social skill for humans.
As with some animals such as dogs and monkeys, sheep are social creatures that can recognise other sheep as well as familiar humans. But not much is known about their overall ability to process faces.
The Cambridge researchers showed the sheep faces from the front initially. But to really put them through their paces, the researchers next showed them the faces at an angle. The sheep’s performance dropped but only by about 15 per cent - a figure comparable to what humans given with the same task have achieved.
The scientists also looked at whether sheep were able to recognise a handler from a photograph without pre-training.
Given that handlers typically spend two hours a day with the sheep, the animals are very familiar with them. When a portrait photograph of the handler was interspersed randomly in place of the celebrity, the sheep chose the handler’s photograph over the unfamiliar face seven out of 10 times.
The researchers witnessed some fascinating behaviour during this task - the sheep did a ‘double take’ when confronted with images including one of their handler for the first time.
First they checked the unfamiliar of the two faces presented, then the handler’s image, and then the unfamiliar face again before making a decision to choose the handler.
Prof Morton’s team recently began studying sheep that had been genetically modified to carry the mutation that causes Huntington’s disease, which affects more than 6,700 people in the UK.
An incurable neurodegenerative disease that typically begins in adulthood, it begins by affecting motor co-ordination, mood, personality and memory, as well as other symptoms including impairments in recognising facial emotion.
Eventually, patients have difficulty in speech and swallowing, loss of motor function and die at a relatively early age. There are ways to manage symptoms but no known cure.
The research was supported by the CHDI Foundation, Inc, a US-based charitable trust that supports biomedical research related to Huntington’s disease.