Why are there so many different types of bats?

Each animal has a niche, a Special job to fill, in africa there are allot of animals. So each bat has evolved for the specific thing that they feed upon. If you look at a lay out of bats, you'll see that most of the bats don't share food sources. This makes sure that food supply doesn't run out for one of the bats and that more then one species of bat Living in a area doesn't have any problems with another, this insure that they can live in harmony.