SHEEP do not behave like sheep in the way most people imagine, research suggests.

When they follow the flock, they are not so much copying each other as acting on their own out of a sense of survival.

Scientists tested the selfish herd hypothesis by strapping GPS satellite tracking devices to the backs of animals being rounded up by a sheep dog.

They said the sheep's herding behaviour was due to an individual drive to escape danger.

A sheep at the centre of a herd is less likely to be eaten.

"In each case, we found the sheep exhibit a strong attraction towards the centre of the flock as the dog approaches," said lead researcher Dr Andrew King, from the Royal Veterinary College, University of London.

With sheep, the researchers were able to use a farmer's dog as a prospective predator.

The findings, published in the journal Current Biology, suggest that individual sheep under threat continuously move towards the centre of the flock. The flock as a whole, mean-while, moves away from the threat.

"It's kind of continuously folding in on itself," said Dr King. The same folding pattern was recreated using a simple mathematical formula.

The study may be useful to other scientists investigating Huntington's disease.

The devastating condition causes personality changes and uncontrollable movements.