Animal Species

There are up to 10,000 species of animals in the world and that's about 3-30 million animals total. They are made up of vertebrates and invertebrates and there are a lot more invertebrates than vertebrates. Biodiversity is the wide range of organisms at all levels of organization. It has to do with genetic diversity with the population. There a lot of different animals and they are all very different.

http://animals.about.com/od/zoologybasics/a/howmanyspecies.htm