There are many different kinds of bats. However, the great majority of them - two-thirds - are insectivores, feasting at night on everything from moths and mosquitoes to beetles and gnats. 

The diet of the other third is varied. Ten species in Central America are carnivorous, including the Noctilio, which plucks fish out of the water, and the Vampyrum, which intercepts birds out of mid-air. Within this group are are also three strains of the infamous vampire bat which, per its name, feeds off the blood of other animals.

A less well-known aspect of the dietary habits of bats is their role in fertilizing tropical forests with fruit seeds and pollinating various kinds of plants. When a pair of researchers for the American Museum of Natural History ventured to Central French Guiana to study the interaction between three dozen species of flower nectar-eating bats and nearly 2,000 different kinds of plants, they were able to divide them into two groups: obligate nectarivorous bats and opportunistic nectarivores. The sheer variety of bats in just this one small geographical area speaks to the great complexity of the species.

In April of 2010, a study by a pair of scientists from the universities of Maryland and California, Irvine concluded that a great deal importance could be attributed in the overall food chain to the consumption of insects by bats. Together with birds and lizards, it was found that the eating habits of bats was responsible for reducing damage to plants by 40 percent, thereby resulting in a 14 percent increase in plant biomass.