Humans versus Animals

The first book I can remember featuring a human-like animal was one of the Curious George books.  Once, The Man in the Yellow Hat took George to the aquarium.  There, he was so curious he climbed the wall and ventured onto the penguin exhibit.  Then, when they went to the beach, he climbed on the lifeguard stand and fed all the crackers to the seagulls.

When I think about it, I'm fascinated that children never question the use of a human-like animal in books.  We never hear of a parent sitting down to read a book and the child saying, "Wait mom.  Wait.  You mean to tell me this animal can talk?  Mom!  Animals can't talk!"  No, children just accept the creativity and go with the flow.  Any other day of the week a child can see another child riding a bicycle, but when a monkey rides a bicycle, wow!  That's cool.

Recently I bought three Curious George books, only to discover that George never talks.  Nope!  He wonders, but never once does the text mention that George said anything.  Though he doesn't talk, it's still entertaining to see George do the silly and mischievous things that a child would do.

When you write children's stories, do you prefer anthropomorphic characters?  Do you mix it up with human and animal characters?  Why?