According to Coren, data from 208 dog obedience judges from the US and Canada showed the differences in working and obedience intelligence of dog breeds.

'Border collies are number one; poodles are second, followed by German shepherds. Fourth on the list are golden retrievers; fifth, Dobermans; sixth, Shetland sheepdogs; and finally, Labrador retrievers,' said Coren.

As for language, the average dog can learn 165 words, including signals, and the 'super dogs' (those in the top 20 percent of dog intelligence) can learn 250 words, he said.

'The upper limit of a dogs' ability to learn language is partly based on a study of a border collie named Rico who showed knowledge of 200 spoken words and demonstrated 'fast-track learning', which scientists believed was only found in humans and language learning apes.'

Dogs can also count up to four or five, said Coren. And they have a basic understanding of arithmetic and will notice errors in simple computations, such as 1+1=1 or 1+1=3.

These findings were presented at the American Psychological Association's 117th Annual Convention.