Just yesterday someone on the street said to me:
"Your dog looks like he’s smiling at me!"
So I was delighted by this article on the BBC site…
Animal laughs no joke says expert
Many animals may have their own forms of laughter, says a US researcher writing in the magazine Science.
"Such knowledge may help to reveal how joking and horsing around emerged"
–-Jaak Panksepp, Bowling Green State University