Study On The Morphology And Phylogeography Of Two Vespertilionid Bats In Hainan

Hainan is the second biggest island of China with the abundant unique wildlife resources. There are 33 chiroptera species in Hainan, 7 species were considered as unique subspecies. Also Hainan is the highest species density regin in China. It means that Hainan is an important region in analysis of phylogeography of chiropterea.Islands have been described as natural laboratories by evolutionary biologists and ecologists alike and have played a pivotal role in the development of these fields, because of the isolation effect by the strait. Since Hainan and main land are separated by Qiongzhou strait, the species in the Hainan islands are much easier to diverge and isolate. But the fact of poor understands and less analysis of Hainan chiroptera species leads lots of uncertainties and misunderstands in the taxmony. Our aim is to exploit the morphological and genetic differences of some vespertilionid bats distributing in Hainan island and nearby regions, to estimate the effect of isolation of Qiongzhou strait and discuss the parttern of thses bats'colonization, throught the methods of the numerical taxonomy and phylogeography.Therefore we studied the the numerical taxonomy and phylogeography of two common vespertilionid bats, lesser Asiatic yellow bat(Scotophilus kuhlii) and bent-winged bat complex (Miniopterus schreibersii complex) in Hainan and nearby regions.The results that the plots of the principle component (referring as pc below) 1 and pc 2 and pc 3 were farraginous indicated lesser Asiatic yellow bat populations of Guangdong and Hainan did not vary significantly, morphologic measurements of 12 external characters and 19 skull characters of Guangdong and Hainan speciements did not show varying significantly (p>0.05), and sugguested that there is no difference between two subspecies because of the isolation of Qiongzhou strait. All the Numerical Taxonomy results indicated that there were few morphological differences. The Hainan's subspecies should be canceled. The molecular data shows similar results. 3 haplotypes were shared by Guangdong and Hainan populations. The AMOVA results indicated that most genetic variation was from within populations (86.16%), two regions (Guangdong region and Hainan region) had only 1.58% genetic variation. Low level of Fst distant and high level Nm (gene flow) indicated that 8 populations from two regions had very little genetic differences. The fact that all the regions with few haplotypes and low nucleotide diversity value indicated there may have had the strong bottleneck effect recently. Moreover we found lesser Asiatic yellow bat migrated periodically to the repuductive habitat, therefore two regions populations may shared one big gene pool because they may migrate to the same site or nearby sites and breeded together. Finially our analysis did not support the existence of Hainan subspecies of lesser Asiatic yellow bat, and we concluded that the Qiongzhou strait had little effect on the divergence of two regions populations.The results of principle component anaylsis of bent-winged bat complex(Miniopterus schreibersii complex)indicated that all the speciements from Hunan, Sichuan, Yunnan formed one group refering as Small Group (Northwestern Group), while the speciements from Guangdong, Hainan and Hongkong formed the other group refering as Big Group (Southern group). The discriminant analysis and univariate analysis also revealed the similar results. But the molecular result was conflicting while comparing the morphoical result. The results of the hapoltypes relation revealed two solid and highly divergent clades, Clade 1composed by all speciements from Guangdong, HainanHaikou, some from Hongkong, and Clade 2 composed by Hunan, Yunnan, HainanWuzhi mountain and Hainan Diaoluo mountain and the rest specimens of Hongkong. The result indicated the clades may be from different lineages. The result that no geographic sturture was revealed within the clades indicated the populations within the same clade may have gene flow or distribute to different habitats from one big population. The results that three Hainan populations came from different clades (lineages), low level Fst genetic distance between the populations within the clade and rejection of IBD model from Mantel test indicated that Qiongzhou strait had little effect on the divergence and isolation. The confliting results of morphology and molecule may be from four reasons: (1) no correlation between the rapid morphogical divergences and the Dloop segment, (2) the rigid maternal inheritance of D-loop segment, (3) diference of habitat resulting in rapid morphogical divergence, (4) morphogical divergences because of hybridization between different lingages.