Are you a top dog, cool cat or Machiavellian chimp?

Anyone who has had a run-in with aggressive thugs may have referred to them, in anger, as resembling apes.

Anyone who has had a run-in with aggressive thugs may have referred to them, in anger, as resembling apes.

Now scientists have established that this term of abuse, implying a lack of evolutionary advancement on the part of the assailant, is in fact an accurate comparison.

In their latest research, psychologists have discovered what any self-respecting pet owner has long assumed – that animals have distinct personalities.

Monkeys, they say, tend to be hostile rather than cheeky. Hyenas are assertive – the Tony Blairs of the animal kingdom – while chimps are said to be machiavellian. Ken Livingstone, anybody?

Hedgehogs are grumpy, like Anne Robinson, bringing a new definition to the term spiky.

Goats, rats, snakes and the octopus also have different personalities.

The research is based on horses, and shows that when the satirist Jonathan Swift imagined a world ruled by civilised horses – the Houyhnhnms – in Gulliver's Travels, he knew more than he was letting on.

It found that both mares and geldings have a range of personalities similar to humans'. There were the neurotics: "Worries a lot, has inferiority feelings and when stressed can be very anxious. Not a horse to feel lonely. Often tense and jittery. Has very low self-esteem." The kind of horse, no doubt, to go into showbiz.

There were the conscientious: "Keeps a neat and clean stable, is reliable and won't let you down."

And the extroverts: "Is cheerful and high spirited, and optimistic. Life for him or her is fast paced." The kind of horse to sell you a nice little runner with hardly any mileage on the clock and one careful owner.

There are also horses open to experience – "Thinks about ideas and abstract thoughts. Is excited by the beauty of his or her surroundings." The Picassos of the equine world.

The research, carried out at the University of Portsmouth, and reported in the Journal of Personality and Individual Differences , was based on a study of what horse handlers had to say about their animals.

"We have demonstrated that a popular and demonstrably reliable personality scale devised for humans is also reliable when applied to horses," say the researchers.

The researchers say the fact that animals have personalities is important because it means some will be better suited to some jobs than others.

A neurotic horse, for example, may not be the best choice for police crowd control, while an agreeable horse would be the best type to have in shared stables.

For other animals too, personality could be an issue.

Disagreeable and excitable dogs, or politicians, are to be avoided, and so too are aggressive cats, and grumpy budgerigars – who in the human world might not be dissimilar to the gaffe-prone Duke of Edinburgh.