I see dogs play tricks on each other, and I know they have a sense of humor.
When I walk two dogs off-lead late at night, one would go on outside of the hedge, and the other on the inside of the hedge. The little one would wait at the end of the hedge to jump out at the other dog, and then just dance around in delight when he scared the older dog.
After a few times, the older dog expected it and stopped acting startled, and the little guy quit doing that. Now they both go on the same side of the hedge.
There are many other incidents that prove they play tricks on each other, but that one happened just last month.