I am sick of how animals are classified. It is too confusing with all the Greek names. I have a simple way of classifying things. Anything that flies will be a bird. Anything on land will be animal. Anything that swims is a fish. It will also be dependent on where that creature is at said time. If a bird is walking on land it will then be an animal. An otter on land would be an animal, but a fish when it is in water. Simple.