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介绍蝙蝠的英文短文蝙蝠的生活习性,食物,生活的环境等

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介绍蝙蝠的英文短文
蝙蝠的生活习性,食物,生活的环境等
介绍蝙蝠的英文短文蝙蝠的生活习性,食物,生活的环境等
Echolocation
In emitting high-pitched sounds and listening to resultant echoes,the process used in radar technology,bats are able to locate prey and nearby objects.This is the process known as echolocation,the ability they similarly share with dolphins and whales.
Two groups of moths exploit a bat sense to echolocate:tiger moths produce ultrasonic signals to warn the bats of that moths are chemically-protective or aposematic.This was once thought to be the biological equivalent of "radar jamming",but this theory has yet to be confirmed.The moths Noctuidae have a hearing organ called a tympanum which responds to an incoming bat signal by causing the moth's flight muscles to twitch erratically,sending the moth into random evasive manoeuvres.
Eyes
Although the eyes of most microbat species are small and poorly developed,leading to poor visual acuity,none of them are blind.Vision is used to navigate microbats especially for long distances when beyond the range of echolocation.It has even been discovered that some species are able to detect ultraviolet light.They also have a high quality sense of smell and hearing.Bats hunt at night to avoid competition with birds,and travel large distances at most 800 km,in their search for food.[2]
Wings
The finger bones of bats are much more flexible than those of other mammals.One reason is that the cartilage in their fingers lacks calcium and other minerals nearer the tips,increasing their ability to bend without splintering.The cross-section of the finger bone is also flattened compared to circular cross section of human finger bone have,and is very flexible.The skin on their wing membranes has more elasticity and so can stretch much more than other mammals.
The wings of bats are much thinner than those of birds,so bats can manoeuvre more quickly and more accurately than birds.It is also delicate,ripping easily.[12] However the tissue of the bat's membrane is able to regrow,such that small tears can heal quickly.[12][13] The surface of their wings is equipped with touch-sensitive receptors on small bumps called Merkel cells,found in most mammals including humans,similarly found on our finger tips.These sensitive areas are different in bats as each bump has a tiny hair in the center,[14] making it even more sensitive and allowing the bat to detect and collect information about the air flowing over its wings,thereby providing feedback to the bat to change its shape of its wing to fly more efficiently.[14] Some bats like the little brown bat can use this dexterious ability where it is able to drink in mid air.[15] Other bats such as the flying fox or fruit bat gently skim the water's surface,then lands nearby to lick water from their chest fur.[16] An additional kind of receptor cell is found in the wing membrane of species that use their wings to catch prey.This receptor cell is sensitive to the stretching of the membrane.[14] The cells are concentrated in areas of the membrane where insects hit the wings when the bats capture them.
Behaviour
Most microbats are nocturnal and are active at twilight.A large portion of bats migrate hundred of kilometers to winter hibernation dens[24],some pass into torpor in cold weather,rousing and feed when warm weather allows for insects to be active[25].Others retreat to caves for winter and hibernate for six months.[25] Bats rarely fly in rain as the rain interferes with their echo location,and they are unable to locate their food.
The social structure of bats varies,with some bats leading a solitary life and others living in caves colonized by more than a million bats[26].The fission-fusion social structure is seen among several species of bats.The term "fusion" refers to a large numbers of bats that congregate together in one roosting area and "fission" refers to breaking up and the mixing of subgroups,where individual bats switching roosts with others and often ending up in different trees and with different roostmates.
Studies also show that bats make all kinds of sounds to communicate with others.Scientists in the field have listened to bats and have been able to identify some sounds with some behaviour bats will make right after the sounds are made[26].
70% of bat species are insectivorous,locating their prey by means of echolocation.Of the remainder,most feed on fruits[27].Only three species sustain themselves with blood.Some species even prey on vertebrates:these are the leaf-nosed bats (Phyllostomidae) of Central America and South America,and the two bulldog bat (Noctilionidae) species,which feed on fish.At least two species of bat are known to feed on bats:the Spectral Bat,also known as the American False Vampire bat,and the Ghost Bat of Australia[27].One species,the Greater Noctule bat,catches and eats small birds in the air.