The Onion make comedy videos, so it wasn't real. I didn't find this funny though, because the gorilla has obviously been trained and is being used for studies.
The Onion made a good video about horse racing. Describing jockeys as 'horse beaters' which is exactly what they are.
I think you will find they are parodying a very famous video of a Gorilla named Coco and how sad and distraught she was when her pet kitten died. She had a pet kitten, fed it, loved it just like a human, but the kitten got out one day and got hit by a car. Coco realised that she was missing and asked the scientists, they signed to her that her kitten died and she signed back "bad, sad bad, cry, frown, sad" its pretty touching to see as you can see Cocos grieving expressions, so human like!
They are amazingly intelligent and can comprehend death, later on in the video they showed that at night Coco actually whimpered and cried, once her trainers had left.
http://www.youtube.com/watch?v=XqTUG8MPmGg