They are the largest living rodent in the world, growing to just over 4ft and weighing 10 stone.

Now the six-strong capybara group at Howletts wild animal park has been swelled by four babies born two weeks ago.

Originally from South America, capybaras are related to agouti, chinchillas and guinea pigs.

They have heavy, barrel-shaped bodies and short heads, no tail, slightly webbed feet and 20 teeth which continue to grow to compensate for the constant erosion from eating grasses.

After a gestation period of between four and five months the female usually produces a litter of four babies but may produce up to eight.

Within a week the babies are able to eat grass although they continue to suckle from any female in the group until around four months.

Their digestive system is very effective with 75 per cent of the diet including only three to six species of plants.