* A: Aardvark, Alpaca, Antelope, Armadillo
* E: Eel, Elephant, Emu, Eagle
* I: Iguana, Ibis, Iguana
* O: Octopus, Ostrich, Orangutan, Otter
* U: Uakari (a type of monkey), Umbrellabird, Uakari (a type of monkey)
That's quite a few! Can you think of any more?