With the number of species and their wide distribution, bats have evolved a number of adaptations. Bat species take a number of forms from the larger frugivorous species to species that weigh less than five grams and prey upon insects. Bats’ roles as pollinators to predators, the variety of food sources and choices of roost locations reflect the range of adaptations bats have evolved.
However, all bats share the unique distinction of mammals that have adapted to flight. Bat wings are entirely different from those of birds or insects. Just as the name Chiroptera (“winged hands”) implies, the bones in the wings of bats are elongated fingers. Imagine that your fingers were much longer and connected by flaps of skin. The wings of bats are similar. Now imagine that that same webbing attaches from your thumb down to your ankle. The webbing between bats’ ‘fingers’ extends to the bats legs to create wings that fold against or wrap around their bodies when roosting. The legs of bats are also connected to the body with the same membrane and often their tails too. These wings, allow for incredible maneuverability in bats. Many species of bats must rely on their ability to catch small quickly moving insects so they themselves must be just as quick and agile!
Another important adaptation found in many species of bats is the ability to hibernate in seasons when weather or food abundance requires them to conserve energy. Although hibernation is generally considered an adaptation by animals that inhabit temperate regions, several tropical species of bats will hibernate as well. It is thought that tropical species of bats have adapted this behavior to cope with low abundance of food, such as seasonal lack of fruit or insects. Even in tropical species, bats metabolism must be capable of reducing the energy requirement of a hibernating individual by dropping the core body temperature and allowing the bat to go into a hibernative state. In some places it is thought that bats achieve this by migrating altitudinally, moving up-slope to cooler elevations.