LOL! Dave Kellett of Sheldon Comics drew this series of totally scientific anatomy charts of various animals. It is highly accurate and 100% correct in every way. He has also done the Anatomy of Dinosaurs, which you can see on his website. You can also support the artist and his comics on Patreon. Here is the Anatomy of Animals:

Artist: Dave Kellett of Sheldon Comics – Support the artist on Patreon!
Colors: Beth Morrell