| There are 117 species of chiropters belonging to 31 genera, 7 families inChina. Their particular echolocation attracts many researchers' focus and interesting. Atpresent, the studies of bats in China mostly focus on these aspects: bats' distribution andclassification; the ecology of bats, including their prey. selection, habitat, theirrelationship, their activity rhythm in day and night, their hibernation and so on; thechemical communication of bats; their reproduction and growth; chromosome andkaryotype; bats as reservior host of virus; physilology and biochemistry; hearing andecholocation, which contain echolocating bats' foraging strategy, audio communication,and the specific of their auditory system; The relationship of echolocation and differentactivity states, ecology niche, body size, sexual differences are also investigated.Meanwhile, the review shows aspects of neurophysiology and neurobiochemistry ofauditory system.The bats in one cave in QinLing Mountain in ZhaShui area of ShannXi wereinvestigated during one year in present research, which contains the echology,morphology, structure of cochlea and hearing function of Hipposideros pratti prattiTomas, Rhinolophus rouxi sinicus Andersen and Miniopterus schreibersi chinensisThomas. Suggestions for future research are also made. The results are summarized asfollows:1.From 2005 to 2006,bats in one cave in ZhaShui area of ShannXi wereinvestigated.We entered into the cave in the daytime in different months of one year,which exclude period of bats' hibernation. The content consist of the species of bats, thequantity of population and the diversification of distribution in different months.According to the records and investigating, bats have the ability to select more suitableliving space of caves for them. They prefer to inhabit caves, which are surrounded withgood vegetation of farmland-grassland. They also like to select the habitats of caves which are more deep, dark, moisture, warmer, low elevation and lesser jamming. At theend of the spring, in summer and at the beginging of the autumn, there is a phenomenonof assembly distribution of Hipposideros pratti pratti Tomas, Rhinolophus rouxi sinicusAndersen and Miniopterus schreibersi chinensis Thomas, which relate with groupforaging and group reproduction. The hiberarchy of distribution of bats bring onremarkable differences of different species in their living spaces. This differentiation ofecology niche is a key for different species living in the same cave. During the end ofspring and whole summer, the number of male is much more than female's. Thismaladjustment of sex ratio may result from migration of bats and their mating system.Rhinolophus rouxi sinicus Andersen is the dominant species, which demonstrate that thehabitat holding good broad-leaved vegetation is a healthy environment. Moreover, togreat extent, jamming and influence of habitat cause the decrease of bat population. Theoutcome above provide the straight evidence and data of distribution of bats in China,which offer some theory basis for bat' protection and discussion of how bats adaptenvironment and evolve.2.Bats living in the same cave in ZhaShui region was identified, described andsome related data also are measured. There are three species of bats, Hipposideros prattipratti Thomas, Rhinolophus rouxi sinicus Andersen and Miniopterus schreibersichinensis Thomas, which are identified by Zoological Institute, CAS.The findings showthat there are some distinctions in morphologic datum and ear related datum amongthese bats inhabiting the same cave, which determine the differences of echolocaioncalls, activity patterns related to hearing, foraging strategy and ecology niche. That is tosay, bats' echolocation activities and their morphologic characters have close connectionwith their foraging strategy and foraging habitat. From the morphologic characters ofHipposideros pratti pratti Tomas, we can conclude that they own the heaviest weight,the longest forearm length, the biggest figure, the longest wing, ear length and ear width.These factors decide that they are fit for long-distance flying, flying quickly andunskillfully. Hipposideros pratti pratti Tomas often forage in complicated region, attacktargets with the bigger shape and the ability of flying quickly, which can meet theirenergy needs. Rhinolophus rouxi sinicus Andersen with the lightweight, short totallength and forarm length, which we can conclude that their flying speed is slow, buthave the skillful flying ability. They can detect the little wing-beating insects incomparative simple condition, such as in dense foliages and narrow habitat around. Miniopterus schreibersi chinensis Thomas has the similarities with Rhinolophus rouxisinicus Andersen, but they ofen prey on in complicated room by gleaning, such as innarrow space. These results provide supplement and proof of morphologic database ofbats in China, and approve the theory again, which bats' echolocation activities andtheir morphologic characters have close connection with their foraging strategy andforaging habitat.3. Bats living in the same cave in ZhaShui region were studied by mensuratingtheir hearing function and observing their aultra-structure of hair cells of cochlea. Byusing Tucker-Davis Technology(TDT)Biosig Systemâ…¢, we gain the result that auditorybrainstem responses(ABR) of bats,which sensitive region is 12-48kHz.This outcome isbasically consistent with the ICR mouse's sensitive region that is 12-32kHz,and thatMicrotus mandarinus's sensitive region is 6-8kHz. The bats' cochlear hair cells wereobserved by scanning electron microscope, and the structure of bats'cochlear is similarto human being's. The inner hair cells (IHCs) of bats resemble any other mammals,which own only one row, and their stereocilia are short. At the basal of basilarmembrane, the stereocilia bundles of IHCs are thin and cuticular plate (CP) separatewith each other. On the contrary, at the apex of basilar membrane, the stereociliabundles are bushy and cuticular plate join together. At the same time, there aresignificant differences between the outer hair cells (OHCs) stereocilia of bats and othermammals's. The stereocilia of OHCs are extremely short. We can observe thephenomena of rupture and inosculation of stereocilia, which is alike senile deafness ofICR mouse. The OHCs bodies of bats have two leading characteristics. Firstly, theOHCs bodies are obviously short. The Deiters cell phalanges are of exaggerated, andthe cup formation of Deiters cell body enwrap the bottom of the OHCs.Secondly, TheOHCs body possess the flask-shaped in the basal turn of the cochlea, which don't likeother mammals'tube-shaped OHCs body. All of the results above indicate that bats andmostly any other little mammals have the similar audiogram in definite range, but alsohave some difference. Echolocating bats always possess of acuity hearing, whichinclude more available frequency. The structure of bats'cochlea is partly resembled withother mammals; meanwhile, there are some specilized aspects, which are considered asmorphologic adaptation to dealing with ultra-high frequency sound wave. All thefindings not only supply helps for the researchesof ethology and neurobiology ofecholocating animals, but also provide suggestions of hearing mechanism and deafness prevention in human beings.
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