The Differences In Phenotypic Characteristics And Small-scale Spatial Genetic Structure Of Sinian Crowbirds In Dafeng Elk Nature Reserve

The reed parrotbill(Paradoxornis heudei)is a medium-sized passerine bird,which is defined as near threatened species by The World Conservation Union(IUCN).They have two subspecies,P.h.heudei and P.h polivanovi.The'P.h heudei is Endemic bird and only found in China.The genetic structure and demography of reed parrotbill were studied thoroughly,but we know little about the fine-scale genetic structure of the reed parrotbill.In this study,we evaluated the sexual dimorphism of reed parrotbill in Jiangsu Dafeng Milu National Natural Reserve,and investigated the fine-scale genetic structure of reed parrotbill population base on the variation of 11 microsatellites.The genetic relationships among individuals within and between the winter groups of reed parrotbills were also evaluated.Eighteen morphological characters including weight,body length,second toe length,second talon length,bill gap length,wing span length,tarsus length,culmen length were chosen for the study of sexual dimorphism of reed parrotbills.The results indicating that there are significant differences between the male and female in body weight and the morphological characters of the beak we selected in this study(P<0.001),and males are larger than females.Total of 113 reed parrotbills were sampled in this study.The high level of polymorphisms was observed in the reed parrotbill population base on 11 microsatellite variation analysis.The average allele number,average expected heterozygosity,average polymorphism information content were 10.82,0.771 and 0.744 respectively,which suggested that they can be used in future investigation of genetic structure and relatedness of this animal.Spatial autocorrelation analysis and two-dimensional local spatial analysis(2D LSA)showed that there was non-significant fine-scale genetic structure in the study areas,and we also did not observed any significant correlations between geographic distance and genetic distance among males or females.The results indicating that there is no sex-biased dispersal in reed parrotbill.Social behavior of group-living animals is often influenced by the relatedness of individuals.Understanding the genetic structure of groups can improve our knowledge of the costs and benefits of social interactions.The genetic parentage and mating system of the reed parrotbill were studied with eleven highly polymorphic microsatellite loci.The result showed that the reed parrotbills is monogamous species,and conspecific brood parasitism may exist in this species.The genetic relatedness and relatedness categories(close kin vs.unrelated)were analyzed,and the results shown that most birds were unrelated to each other in the winter flocks,although all individuals had at least one close relative in their own flock.The result indicating there are low average relatedness coefficients between winter flocks.