What is a bat? Isn't it just a flying a rat?

Often people think bats are 'bugs,' birds, or rodents. Bats are certainly neither bugs (which as insects do not have an internal skeleton), nor are they birds which are actually related to dinosaurs. Instead like rodents bats are Mammals and do all sorts of mammal things like give birth to young they nurse. Additionally like other mammals they have hair, four-chambered hearts and different kinds of teeth. However, they are more closely related to us (Primates) or to a hedgehog (Eulipotophyla) then they are to a mouse. However the common assumption that they are mice or rats (Rodents) is reflected by the word for bats which in many languages includes reference to 'mouse' or 'rodent.' For example in German the word for bats is Fledermaus which literally translated means filtering mouse.

However, for a substantial period of time bats have been placed in their own Order (i.e. a taxonomic group) just like Rodents. The name of the Order bats are in is Chiroptera which means 'hand' and 'wing' based on the origins of their powered flight (see my evolution of flight post). Bats are further divided into two types which are referred to as Suborders. These two groups are the Megachrioptera and Microchiroptera.

Members of the Megachrioptera (a group of closely related species) are the largest bats. Mega is a Greek prefix meaning 'large' which refers to their large size. The species in this group are sometimes called flying foxes (see picture below to see their 'fox-like' faces) and are found in Australia and the South Pacific. Sometimes these bats are also called 'Fruit bats' given that nearly all of them rely entirely on fruit but this name is confusing because many Microchiroptera also eat fruit (for example my study species the Jamaican fruit bat and its relatives).

Microchriptera (aka 'Micro bats') however are generally small as their name suggests (Micro is a Greek prefix meaning 'small'). These closely related bats are usually very small but sometimes can be as large as small Megachiropterans. They are also nearly cosmopolitan in distribution (meaning they occur globally). They are found from the far north in places such as Alaska and Scandinavia to the extreme South such as South Africa, and Southern South America and are pretty much everywhere else between! An example of a Micro bat is shown below.

Microbats are much more diverse but both groups present amazing examples of the diversity of vertebrates as the only flying mammals!

*Images are from the American Society of Mammalogists website where you can access many other excellent photos of different mammals.