The thumb is a tiny hook on top of the wing. The wing membrane connects with the body, back legs, and, in most bats, encloses the tail. Cave bats weigh very little, less than an ounce. Bats can live up to 25 years and usually have only one young each year. As with other mammals, the baby bat is born alive and is fed milk by the mother.
Females often nest in large colonies.
They roost in caves during the day, preferring dome shaped ceilings for safety from predators. Roosting bats hang by their feet with their wings folded around them. Many people think that bats are dirty and carry diseases. Bats are actually clean and almost disease-free animals. And yet, people are concerned that all bats carry rabies.