Rats 'like a laugh'

Scientists say giggling, ticklish rats have provided them with the first credible evidence that animals unrelated to humans can laugh.

For years biologists have known that chimpanzees and even some monkeys produce a panting noise akin to human laughter.

But there is scant evidence that other animals are capable of laughter.

Now two American scientists are claiming to have discovered that rats "laugh" when tickled.

Whole story here and a youtube video here for all ya'll who'd rather watch than read :)