1Sometimes the hoatzin is called a stinkbird because it smells so bad. It also has claws on its wings and flies poorly because it's digestive system is too heavy. What an interesting bird! This book highlights cool animals that fly in the air, from hummingbirds to bats to many kinds of birds. Readers won't be able to stop turning pages to find out weird, gross, and awesome facts about each featured animal. And, they won't be able to stop themselves from telling all their friends what they learned!