Do animals have sense of humor?

yes animals have a sense of humor, not only they understand the "jokes", they are also laughing and even making tricks. 

you can read here about the research, and you can check out here
7 stories of animals which have a sense of humor.  

I disagree with Juno animals may laugh but they can not appreciate humor, because the humor you probably refer requires a high level of appreciation of a situation, even if it is a very simple for of humor. Animals do not have this same analyzing quality therefore they can not have a sense of/for humor.

I find the fact that some people do not have a sense of humor is much more disturbing.

I agree with duck.

Animals can do tricks  to entertain themselves and others. Animals can 'play'.

But that's not exactly humor. Animals are usually performing tricks because they know you'll laugh and give them soem food or love or something.

Animals in the wild 'play' but it's not for the same purposes you and I would play. Their reasons range from combat practice to dominance over other kids.

You don't see adult lions play fighting or a sealion in the wild balancing a ball on his nose to entertain his peers.

There is no animal on Earth other than human beings and Yetis that can understand an episode of the Dave Chappelle show and find some humor in it.

I guess you two don't have a dogs.

I had a dog for 15 years and every time I took him with his belt for a walk, he started to circle trees and pulled me with the purpose that I will circle the trees with him, and then he had a big smile on his face.

maybe he was an evil dog, but he had a good sense of humor.   

It may seem so, especially when highly-developed animals, such as chimps and dogs exhibit responses that seem to appreciate the incongruity of a situation. I haven't read any studies on this subject, but I suspect that some animals have learned to react according to cues received from humans - like a toddler who doesn't get the joke but has discovered that when he laughs along with the adults they pay him extra attention.

A sense of "fun" or play is evident in animals, especially young ones, who seem delighted when engaged in interactive freeform running and roughhousing. We had a marvelous black Lab mix who had a canny ability to differentiate between two uses for the same device - a rubber dog pull-toy (see photo).

There were times when "Macho" wanted a vigorous game of give & take, pull and twist, when he would bring the pull-toy to me shaking it in his teeth amid low, good-natured growling. Then there wer times - usually when there were several people present when we would say, "Make a funny face", and he would proceed to wrap the toy around his snout so that it ended up looking like a catcher's mask - at which point he affected a stance that seemed to say, "How do you like me now?"

The more we encouraged him with sounds of exclamation, laughter, pointing and clapping, and, of course, "Good DOG!" - the more eager and excited he was to entertain us.

I don't think dogs have the cognitive function or whatever that can discern irony or humor, but they have learned to react in ways that mimic our behavior and please us.

Mach also had an extensive understood vocabulary. But that's another story...

Since the ability to enjoy humor is based on one's capability to define himself as different from others, animals (and human babies as well) are considered as "humorless".

But from time to time scientists report on various behaviors of animals which seem to express laugh and amusemsnt.

Oh yes. One good example that is very funny is the monkeys. The way they behave, the way they do things and their reactions when they see people around, they make us laugh, especially the kids.

No. We think they are funny because we have the intellectual capacity to think they are funny.