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Shannon O'Donnell asked in the comments of my post about my specialty for ideas for a picture book animal MC that hasn't been overdone.
This is a great question. To be fair, I'm not 100% up-to-date on picture books, but I can throw out some unusual ones, and hopefully they haven't been done yet. Story is, of course, up to you! (Note: I tend to lean towards predators, only because I think they're AWESOME, but I'm not sure how this would go over for kid's books. Wouldn't want Jr. to walk up to a bear and go, "Oh! It's Bubba the Bear!" and get eaten. That would be bad. However, I'm assuming you know all about it, and I'll try to include some animals that wouldn't, you know, eat your readers if they met in an empty field).
-Manticore (kidding! Just seeing if you're paying attention)
-Gorilla or other monkey/ primate
-Tyrannosaurus Rex (no Velociraptors, though)
Any good ideas in there? I hope so. Let me know if not, I can rattle off a few more.