Descriptionmuch. They are good for two things: being eaten and producing wool.Reality: Sheep are actually surprisingly intelligent, with impressive memory and recognition skills. They build friendships, stick up for one another in fights, and feel sad when their friends are sent to slaughter. They are also one of the most destructive creatures on the planet.Intelligent. Complex. Sociable. All words we would quickly assign to humans, but would not dream of extending to sheep, those fluffy white creatures you see milling about in fields – or served up with mint sauce on your dinner plate.Instead, we have decreed that sheep (Ovis aries) are just plain stupid. This opinion has not changed much since the 1700s, when George Washington, one of the Founding Fathers of the United States of America, declared: "If the freedom of speech is taken away then dumb and silent we may be led, like sheep to the slaughter."Nowadays, to be "a sheep" is to be someone who mindlessly follows others: "a waste of flesh and brain cells," as Urban Dictionary puts it.The truth is that sheep are far smarter than we know.A 2001 study by Keith Kendrick, who is now at the University of Electronic Science and Technology in China, found that they can recognise and remember at least 50 individual faces for more than 2 years. That is longer than many humans.In the study, Kendrick's team trained sheep to distinguish between 25 pairs of sheep, by associating one member of each pair with a food reward.Sheep showed clear behavioural signs of recognising… individuals by vocalising in response to their face pictures," says Kendrick. The team also found evidence that sheep can differentiate facial expressions, and prefer a smile to a frown.At the time Kendrick told BBC News: "The way the sheep's brain is organised suggests they must have some kind of emotional response to what they see in the world."Caroline Lee of the CSIRO in Australia has also studied sheep intelligence. She discovered that sheep can learn how to navigate out of a complex maze. The enticing sight of their fellow sheep friends awaiting them at the finish helped them reach the exit.Aside from being smart, sheep can be playful and joyful. You only need to watch the video of Winter the Jumping Lamb to see for yourself. Sheep also have erotic preferences: 8% are homosexual, making them one of the few species that show lifelong preferences for same-sex partners.Sheep also have complex social structures.Over two decades ago, researchers from the University of California observed rams for three years and discovered that they established firm friendships and looked out for one another in times of need: "Rams were found to form long term relationships… [they] intervened on behalf of weaker colleagues and supported each other in fights," says the 1993 study.These acts of loyalty and friendship-building are driven by emotions. A 2009 report published in Animal Welfare found that sheep are capable of experiencing a whole range of feelings, from fear to anger, despair, boredom and happiness.The researchers gave sheep intermittent access to food from a trough, and then turned on an air blower above the trough at an unexpected moment while they were eating. After the blower came on, the sheep bleated four times more than sheep that were not disturbed, and their heart rates immediately increased."[As with humans], despair is triggered by situations which are evaluated as sudden, unfamiliar, unpredictable… and uncontrollable, whereas boredom results from an overly predictable environment," write the authors.}It is ironic how little most of us know about sheep, given how deeply entrenched they are in human culture. They were domesticated between 11000 and 9000 BC for the use of their woollen fleece, meat and milk. The animals have been referred to by different cultures, religious texts and even astrology for thousands of years.