Mike might look angry, but he is actually smiling for the camera!

Some people think gorillas look fierce, but in fact they can be the gentlest creatures around.

Gorillas have been seen petting and playing with frogs and other small animals. The silverback himself lets kid gorillas crawl all over him and tease him like crazy. And Dian Fossey, a researcher who studied gorillas in Zaire and Rwanda, once saw a silverback pick up a flower and tickle a young gorilla with it.