Bats are one of the most widely distributed groups of mammals, and are found on every continent except Antarctica. They are classified as chiroptera which comes from the Greek words "cheir" and "pteron", meaning "hand' and "wing" respectively.
There are two types of bat: microbats and megabats. Microbats use echolocation, while megabats have good eyesight. Microbats also lack a claw on their second toe and underfur. Megabats eat fruit, nectar or pollen, while most microbats eat insects, with some feeding on blood, small animals, fruit, pollen or nectar.
Bats are famed for being able to hang upside down and will even spend months in a state of torpor in this pose.
Although you would think that this must get tiring, the bats employ a special technique which makes this remarkably efficient. Bats have an elastic tendon that locks their claws into a closed position. This means that it requires no muscle power to grip onto cave walls or trees when they come to roost.
Contrary to popular belief, although some microbats have poor, underdeveloped eyes, none are actually blind.
Echolocation is the emission out of a pulse of sound and interpretation of the returning echoes. Bat brains are able to produce detailed 3D images of their surroundings allowing for the detection of prey.
Bats in Mythology
Ever since Bram Stoker's novel Dracula cemented them into the realm of horror, bats have suffered from a bad reputation. However, it all started with the first reports of vampire bats from Spanish Conquistadors on their return from South America.
These vampire bats were reported to be giants, but they were confused with larger nectar-eating relatives, and many bats were erroneously labelled with the "vampire" status. The nose structures on leaf-nosed bats were also reported to be a hard puncturing structure for drawing blood, but in fact there function is for echolocation.
We now know that there are only 3 species of vampire bat, being a relatively small, round bat, with the first being successfully and accurately defined by Charles Darwin while on his expedition on HMS Beagle. Vampire bats are now know to be an incredibly remarkable species, with anticoagulant spit that is helping stroke victims and socially sharing their food with less-successful roost-mates.
Bats are the only mammals capable of true powered flight and represent approximately one fifth of all mammals worldwide. This comes to over 1,240 species!
Bat wings are incredibly sensitive, measuring the air currents as the move across it. Their wings are supported by their extremely elongated digits. While flying, birds flap their entire forelimbs, bats instead flap only their digits.
White Nose Syndrome has contributed to the deaths of more than a million bats in the USA, becoming a major concern. White fungus found grows around their faces and wings of some affected bats leading to the subsequent death of the affected.
- Vampire bats can drink 40% of their body weight in blood in one night.
- Bats represent approx. 20% of all mammals worldwide.
- An elastic tendon locks the bat's claws into a closed position to make hanging more efficient.