Diversification Mechanism Of Horseshoe Bats (Rhinolophidae:Rhinolophus)

Speciation is a basic evolutionary process,which plays a fundamental role in the formation of biodiversity.Early studies of speciation mainly rely on fossil information,so that speculated about the inside and outside mechanisms of speciation.The lack and incomplete of fossil material had decision in some groups can not be reconstructed detailed and credible diversification pattern.In recent years,based on using molecular evolution theory and analysis techniques to study the phylogenetics and species diversification.It will not only be able to rebuild the relationship among different species,but also to reveal the divergence time of species,diversification trend and heterogeneity on lineages.The phylogenetic tree can be used as a skeleton of phylogenetic evolution.By integrating the interdisciplinary,multi-angle information,it is necessary to reconstruct the evolution process and historical biological diffusion events.Finally,analyzed the relationship among whole or local characterization,biogeographic events and history environmental change and species diversification pattern,revealing the mechanism of diversification in specific groups.Among Chiroptera,Rhinolophus are the second genus behind the Myotis,which has reported more than 70 species so far.After a long evolutionary process,this group has different phenotype(e.g.,Body size,noseleaf,skull,teeth,wing morphology and echolocation to adapt different habitat,so this group is an indispensable material to carry out species diversification mechanism.Recently,with the accumulation of sequence data and carry out science and ecology at home and abroad Rhinolophus phylogenetics development,explore this genus diversification mechanisms have been initial maturity.In this study,we used modern methods of molecular biology and bioinformatics to reconstruct a molecular phylogeny and the biogeographic history of Rhinolophus.Our results provide a framework to solve some controversial problems in taxonomy,and help elucidate evolutionary relationships within the genus.Moverover,the biogeography analysis provides insights into the origin and evolution of distribution ranges of Rhinolophus.The main findings are summarized as follows:1)The phylogenetic relationship of the genus Rhinolophus was basically solved.Through world-wide distribution of species of Rhinolophus,we collected 61 taxa of the genus Rhinolophus.These taxa covered all the sections of subgenus major global distribution zones of the genus.Then we present a better-resolved phylogenetic hypothesis for 61 horseshoe bats based on Maximum Likehood and Bayesian Inference of 26 genes fragments.Strong support was solved the relationship between the main branch of the genus Rhinolophus and found for existence of two geographic clades within the monophyletic Rhinolophus: a Southeast Asian clade and an African clade.2)The middle Eocene period(48.4 Mya)in Asia were suggested the time and origin center of the genus.Based on uncorrelated lognormal relaxed clock and incomplete fossil records,we conducted divergence time estimation and ancestral area reconstruction of horseshoe bats.The results suggested the area of origin,migration and dispersal routes of horseshoe bats.The results from Dispersal-ExtinctionCladogenesis(DEC)analysis suggest that the horseshoe bats arose in Asia and subsequently dispersed from Asia to Southeast Asia and from Asia to Africa then to Europe.3)The pattern of phenotypic evolution in genus Rhinolophus and the ancestral character state were found in this study.Through the diversification rate analysis of horseshoe bats,it was found that the diversification of horseshoe bats was consistent with the adaptive radiation,and we inferred that the decrease of the diversification rate was due to the increasing competition.Rates of all biotic traits divergences were decoupled from species diversification which implies stability of trait divergences in early phase and dramatic divergence in the following period,so that let the horseshoe bats escape from competition.4)The competition among populations of Rhinolophus plays an important role in diversification.A strong negative correlation of diversification rate and overlap area,which is associated with the degree of competition.The niche was interaction with morphology,both of they were no significant relationship between the diversification rate.