The mind of a two-year-old

This afternoon Liam and I were reading books that had large pictures of animals.  The animals themselves weren't necessarily large, but the picture filled the page and most of the time, the animal's mouth was open.  

Liam would stick his finger "in" the animal's mouth, pull it out quickly, and say "ouch" while shaking his hand.  It was really cute.  He started it with a picture of a flying dinosaur and continued it with other animals, especially the ones that had teeth.

I wonder where he gets it from.

And, just because the post needs a picture: