Border Collies demonstrate the art of herding ducks during a British dog show. Dogs are probably much cleverer than most people think, according to a new study.

Scientists are convinced that dogs can count and
researchers at the University of California Davis say they try to convey different messages through the pitch and pace of their barks.

"Animal behaviorists used to think their bark was simply a way of getting attention. Now a new study suggests that individual dogs have specific barks with a range of meanings," New Scientist magazine said on Wednesday.

Dogs usually use high-pitched single barks when they are separated from their owners and a lower, harsher superbark when strangers approach or the doorbell rings, according to Sophia Yin, an animal behaviorist at the university.

Playful woofs are high-pitched and unevenly spaced.

Dogs also know when they are being short-changed on treats because they have a basic mathematical ability which enables them to tell when one pile of objects is bigger than another.

"But to count, an animal has to recognize that each object in a set corresponds to a single number and that the last number in a sequence represents the total number of objects," New Scientist added.

(Agencies)