The Probert Encyclopaedia of Nature

BAT

A bat is a nocturnal, wing-handed, flying mammals, having the forelimb peculiarly modified so as to serve for flight, and constituting the order Cheiroptera (Chiroptera). Bats are sub-divided into two groups; Megachiroptera (the megabats) and Microchiroptera (the microbats).

Bats are structurally not very different from typical mammals except for the extension of their finger bones to carry flight membranes, and their backward bending knees, though their conquest of the air is a marked difference. Echolocation in bats is associated with large ears and in some cases facial skin growths, and the ability to catch flying insects at night. This food source is seasonal, which, combined with their small size, has favoured the evolution of hibernation. Daily torpor, in which the body temperature drops to the ambient temperature is common among temperate bats, and is another energy-saving adaptation necessitated by small bodies engaged in such a high energy activity as flying. Short migrations to roosts of appropriate temperatures occur throughout the year. Mating begins in the autumn, and continues at intervals throughout hibernation. Sperm is stored and ovulation and fertilisation take place in the spring with a typical litter of just one young occurring. The parent shows a strong degree of attachment for her offspring, and when they are captured, will follow them, and even submit to captivity herself rather than forsake her charge.

Bats are common in temperate and warm regions. but are most numerous and largest in the tropics. All European bats are small, and have a mouse-like skin. The body of the largest British species, Vespertilio noctula, is less than that of a mouse, but its wings stretch about 38 cm. During the day it remains in caverns, in the crevices of ruins, hollow trees, and such-like lurking-places, and flits out at evening in search of food, which consists of insects.

Several species of the same genus are common in North America, Many bats are remarkable for having a singular nasal cutaneous appendage, bearing in some cases, a fancied resemblance to a horse-shoe. Two of these horse-shoe bats occur in Britain. Bats may be conveniently divided into two sections - the insectivorous or carnivorous, comprising all European and most African and American species; and the fruit-eating, belonging to tropical Asia and Australia, with several African forms. An Australian fruit-eating bat (Pteropus edulis) commonly known as the kalong or flying-fox, is the largest of all the bats; it does much mischief in orchards. At least two species of South American bats are known to suck the blood of other mammals, and thence are called 'vampire-bats' (though this name has also been given to a species not guilty of this habit). The best known is the Desmodus Rufus of Brazil, Chilli, etc.
Research Bat