Dogs Can Count, Say Scientists

3:55pm UK, Wednesday July 31, 2002

Dogs are probably cleverer than 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.

A not-so-dumb blonde

"Animal behaviourists 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 says.

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

Total number

"But to count, an animal has to recognise 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.

Robert Young of Brazil's Pontifical Catholic University of Minas Gerais in Belo Horizonte, tested the theory on 11 mongrels using dog treats.

The canines were shown treats and then a screen was lowered and the goodies were left as they were or some were added or taken away.

If a treat was added or taken away the dogs looked at the treats much longer than they did when the goodies were not disturbed, presumably because they had done their sums and the numbers did not meet their expectations.