Do animals laugh?

Question

Do animals laugh?

Answer 1

Yes, great apes, like bonobos, truly laugh.  When they get tickled or play with each other, they actually laugh.

Answer 2

The above answerer is wrong, as although the noises made by the Kookaburra and the Hyena are similar to that of a laugh, they are not actually laughing, but signaling in their own way.

I believe that other animals do laugh, but it is near impossible to tell.

Answer 3

Cookaburra's do and so does Hyena's.