Origins & Relatives
Bat fossils have been found that date back about 50 million years. Surprisingly, the bats of that ancient era very closely resembled those we know today. Bats have been around for a very long time. Before humans began to affect their numbers, bats were extremely abundant.
In some places, they probably dominated the night skies just as passenger pigeons filled the daytime skies of the eastern United States until the mid-nineteenth century. In the evolution of nature's system of checks and balances, bats long have played essential roles, and their loss today could compromise the health and stability of our environment.
Bats are mammals of the taxonomic order Chiroptera, which means hand-wing. All living bat species fit into one of two major groups, the Microchiroptera or the Megachiroptera. Members of Megachiroptera are commonly referred to as flying foxes because of their fox-like faces. They are found only in the Old World tropics, while the Microchiroptera, which are highly varied in appearance, occur worldwide.
Like humans, bats give birth to poorly developed young and nurse them from a pair of pectoral breasts. In fact, Linnaeus, the father of modern taxonomy, was so impressed by the similarities between bats and primates (lemurs, monkeys, apes, and humans) that he originally put them into the same taxonomic group. Today's scientists generally agree that primates and bats share a common shrew-like ancestor, but belong to separate groups.