The Sex-biased Dispersal Of Omei Treefrog(Rhacophorus Omeimontis)

Dispersal is a persistent movement of animals that leaving from their birth place to breeding place,and dispersal is a crucial component of population dynamics.Due to the effects of numerous evolutionary factors,female and male animals existed sex-specific dispersal strategies.Actually,quantifying and measuring the strategies of sex-biased dispersal across animal kingdom is difficult.The studies of sex-biased dispersal on birds and mammals have been comparatively sufficient.However,researches of sex-biased dispersal on amphibians are still limited.Therefore,it is especially important to investigate the pattern of sex-biased dispersal in amphibian species and to elaborate its evolutionary mechanism in amphibians.In this study,we selected the Omei treefrog(Rhacophorus omeimontis)as our research object to estimate the pattern of sex-biased dispersal in amphibians,by using different study scales.On the large scale,we applied the analysis in five different geographical populations of R.omeimontis(BX,SC,LJS,HN and PB).We used matrilineal inherited mitochondria genes(cytochrome b and NADH dehydrogenase subunit 2)and the polymorphic biparentally inherited microsatellite markers(9 loci)to carry out the analysis,by comparing the data between mtDNA and microsatellites among five populations through pairwise FST,and to analyze the dispersal preference for each sex by using the microsatellite data through the parameters such as Hs and r.On the fine scale,we performed the analysis with only one R.omeimontis population at Badagongshan Natural Reserve in Hunan Province using microsatellites by the parameters of dispersal like mAlc and vAlc for different sexes.In addition,our team used field observation and individual tagging to find out the numbers and rates of the recurrent individuals for males and females every year(2011-2014).We established that R.omeimontis displayed high genetic diversity.The dispersal rate was higher in,male R.omeimontis than in females.Females revealed a preference of philopatry and males preferred to disperse in Omei treefrog.So we verify that the R.omeimontis exists a significant pattern of male-biased dispersal,by both large scale study and fine scale analysis.Based on our research findings and previous studies of the breeding behavior and mating system in R.omeimontis,we deduced that male competition for rare mates may play a vital role in determining the male-biased dispersal pattern,by cost-benefit dynamic.Thus we speculated that the the local mate competition is the main mechanism to explain the male-biased dispersal pattern in R.omeimontis.This study will be conducive to enrich the cases of studies on amphibians' dispersal.It will be helpful for the behavior evolution researches of R.omeimontis in future.Meanwhile it can do some help to enhance population viability and conservation for amphibians.