Bats

Bats

There are more than 1,000 different kinds of bats, which makes up around 20 per cent of all the known mammal species. Bats are amazing flying mammals. Most species are nocturnal and emerge at night to feed on fruit or insects. Some bats navigate in complete darkness using a sophisticated system called echolocation.

Bats can fly because their front limbs have been modified into wings. The wings are formed from a membrane of skin, called the patagium, which stretches between the four long fingers of each limb and the side of the bat`s body. Bats do not flap their entire wings like birds; instead, they flap the long fingers that form the framework for the wings. This provides the lift forces to fly around obstacles and chase down prey.

The family name for bats is “Chiroptera”, which comes from the Greek Kheiro and pteron, meaning ‘hand wings’. There are two main groups of bats are:-

1. Mega-bats, and

2. Micro-bats.

Mega-bats

As their name suggests, they are mostly larger species that feed mostly on fruit, but also nectar and pollen. For this reason, they are also known as fruit bats. They are also known as flying foxes because their large eyes, pointed ears and long snouts make them look like foxes. Mega-bats live in tropical rainforests, where they feed on the plentiful supply of fruit.

Micro-bats

They are much smaller than fruit bats. Most species hunt insects, although some larger species will eat small fish, frogs or lizards. Three bat species, the aptly named vampire bats, feed on the blood of other animals, including humans. Micro-bats have small eye and rely on echolocation to find food. Although their eyesight is not as well developed as that of mega-bats, their vision is especially sensitive to low light situations.

Most micro-bats have very small eyes so they need another sense to fly and locate prey in complete darkness. Here it is quite interesting to know that, instead of eye, they rely on a technique called echolocation, which means they can ‘see with sound’. As bats fly, they emit a series of clicks. The clicks are high- pitched ultrasound waves that bounce off objects such as the side of a cave wall or prey such as a moth. The bat detects the sound reflections or echoes to find its way around or home in on its prey. A bat chasing a moth will listen for the echoes getting closer together as it approaches, eventually homing in and snatching up its victim. Micro-bats have special body features to help detect the echoes. Some have long, pointed ears, which channel sound waves. Others have a growth called a nose leaf on the face, which helps to focus sound.

Many species of bats are at risk. In tropical regions, farmers are clearing the forests for agricultural land and wiping out populations of flying foxes at the same time. Bats are also seen as pests in many countries since they eat such large quantities of fruit. Some farmers have fumigated roost sites to kill off bat numbers and protect their crops. Many people associate bats with negative images, including blood sucking vampires and vectors for disease.

Reference

1. Britannica Reference Encyclopaedia

2. Knowledge Encyclopedia Animal!: The Animal Kingdom as you've Never Seen it Before

3. Images are taken from Zoo-Que and Google.

4. In Defense of Plants: An Exploration Into the Wonder of Plants

5. A Naturalist’s Guide to the Birds of India

6. Earth: A Sustainable Planet

Also See

• Migration & Navigation of Birds

• Archaeopteryx – The First Bird`s Fossil

• Parrots

• Bats