Study On The Speciation For Jankowski's Bunting(Emberiza Jankowskii) And Meadow Bunting(Emberiza Cioides)

This thesis studies the species differentiation of Jankowski's Bunting(Emberiza jankowskii)and Meadow Bunting(Emberiza cioides)from three aspects: morphology,sound and molecule.The results show that in the morphological analysis,there are significant differences in the wing length,beak height,body length,head height and tail length of E.jankowskii and E.cioides.There are no significant differences in other morphological parameters.Compared with the two,the E.cioides is slightly larger.In the song analysis,there is no significant difference between E.jankowskii and E.cioides except for the duration.Among them,the singing of E.cioides lasts longer,which implies that there are differences in the sentence structure between E.jankowskii and E.cioides,which still needs further research.After analyzing the differences in the individual voice characteristics of E.jankowskii in the Gahaitu area and the Chagantao Ligao region,it is found that there are significant differences in the sentence time interval between the two,which implies that E.jankowskii in different regions there is a micro-geographical variation of the song.After analyzing the genetic diversity using mitochondrial markers,it was found that in the D-loop gene sequence,the haplotype diversity(h = 0.84,SD = 0.02)and nucleotide diversity(? = 0.0030,SD = 0.0002)of E.jankowskii is higher than E.cioides(h = 0.71,SD = 0.01;? = 0.0025,SD = 0.0002).In the ND2 gene sequence,the haplotype diversity(h = 0.94,SD = 0.01)and nucleotide diversity(? = 0.0062,SD =0.001)of E.jankowskii are also higher than those of E.cioides(h = 0.52,SD = 0.11;? =0.0008,SD = 0.002).The calculation of the time of the nearest common ancestor of the two species shows that the nearest common ancestor of E.jankowskii and E.cioides lived 1.36(95% HPD = 1.05–1.70)million years ago.During this period,China is in the transitional period of "Poyang-Poyang-Dagu Interglacial Period-Dagu Glacial Period",which is the glacial-interglacial period.Among them,the nearest common ancestor of all haplotypes of E.jankowskii can be traced back to 0.23(95% HPD = 0.15– 0.31)million years ago,and the nearest common ancestor of all haplotypes of E.cioides can be traced back 0.15(95%HPD = 0.15-0.31)million years ago.This study shows that the morphology and sound of E.jankowskii and E.cioides have not yet fully differentiated,suggesting that ecological selection and sexual selection are not the main reasons for the differentiation of the two.The climate change during the Quaternary glacial-interglacial period the isolation from different refuges may be the main driving force leading to the species differentiation between the two.