Population differentiation is a fundamental process of evolution, and many evolutionary studies, such as population genetics, phylogeography and conservation biology, all require the inference of population differenti...Population differentiation is a fundamental process of evolution, and many evolutionary studies, such as population genetics, phylogeography and conservation biology, all require the inference of population differentiation. Recently, there has been a lot of debate over the validity of FST （and its analogue Gsr） as a measure for population genetic differentiation, notably since the proposal of the new index D in 2008. Although several papers reviewed or explored specific features of these statistical measures, a succinct account of this bewildering issue with an overall update appears to be desirable. This is the purpose of the present review. The available statistics generally fall into two categories, represented by Fsv and D, respectively. None of them is perfect in measuring population genetic differentiation. Nevertheless, they each have advantages and are valuable for current re- search. In practice, both indices should be calculated and a comparison of them can generate useful insights into the evolutionary processes that influence population differentiation. FsT （GsT） has some unique irreplaceable characteristics assuring its standing as the default measure for the foreseeable near future. Also, it will continue to serve as the standard for any alternative measures to contrast with. Instead of being anxious about making choice between these indices, one should pay due attention to the equili-brium status and the level of diversity （especially Hs） of the populations, since they largely sway the power of a given statistic to address a specific question. We provide a multi-faceted comparative summary of the various statistics, which can serve as a basic reference for readers to guide their applications [Current Zoology 61 （5）： 886-897, 2015].展开更多
East Africa is a biodiversity hotspot. Haplocarpha rueppelii （Sch.Bip.） Beauverd is mainly distributed in the alpine grassland of East Africa. Here we sampled 65 individuals of eight populations/locations of H. ruep...East Africa is a biodiversity hotspot. Haplocarpha rueppelii （Sch.Bip.） Beauverd is mainly distributed in the alpine grassland of East Africa. Here we sampled 65 individuals of eight populations/locations of H. rueppelii including hairy and glabrous forms from Mts. Elgon, Aberdare, Kenya, Kilimanjaro and Bale Mountains. We then sequenced one nuclear and three chloroplast DNA fragments and conducted phylogeographic analyses to test the taxonomic rank of the two forms and causes for the differentiation （intrinsic reproductive isolation and geographic barrier）. The results demonstrate that the species consists of two major groups, one includes the populations from Mts. Elgon, Aberdare and Bale, while the other includes Mts. Kenya and Kilimanjaro. The species has established in Mts. Kenya and Aberdare during the Pleistocene. However, migration rate for individuals between the two mountains was low as showed by gene flow analysis. A barrier for plant dispersal and gene flow would have existed between Mts. Aberdare and Kenya since at least Pleistocene. No change of the taxonomic concept of this species is needed. This study reveals a potential geographic barrier in East Africa. We hope it will arouse more scientists＇ interests in phylogeography and biodiversity of East Africa.展开更多
Abstract The Labeoninae is a subfamily of the family Cyprinidae, Order Cypriniformes. Oromandibular morphology within the Labeoninae is the greatest among cyprinid fishes. Although several phylogenetic studies about l...Abstract The Labeoninae is a subfamily of the family Cyprinidae, Order Cypriniformes. Oromandibular morphology within the Labeoninae is the greatest among cyprinid fishes. Although several phylogenetic studies about labeonines have been undertaken the results have been inconsistent and a comprehensive phylogeny is needed. Further, an incongruence between morphological and molecular phylogeny requires a systematic exploration of the significance of morphological characters on the basis of the molecular phylogeny. In this study, a total of 292 nucleotide sequences from 73 individuals （representing 24 genera and 73 species） of Labeoninae were analyzed. The results of the phylogenetic analysis indicate that there are four major clades within Labeoninae and three monophyletic lineages within the fourth clade. Results of the character evolution show that all oromandibular morphological characters are homoplastically distributed on the molecular phylogenetic tree and suggests that these characters evolved several times during the history of labeonines. In particular, the labeonine, a specific disc on the lower lip, has been acquired three times and reversed twice. These morphological characters do not have systematic significance but can be useful for taxonomy. The results of biogeography suggest that the Labeoninae originated from Southeast Asia and separately dispersed to Africa, East Asia and South Asia.展开更多
文摘Population differentiation is a fundamental process of evolution, and many evolutionary studies, such as population genetics, phylogeography and conservation biology, all require the inference of population differentiation. Recently, there has been a lot of debate over the validity of FST （and its analogue Gsr） as a measure for population genetic differentiation, notably since the proposal of the new index D in 2008. Although several papers reviewed or explored specific features of these statistical measures, a succinct account of this bewildering issue with an overall update appears to be desirable. This is the purpose of the present review. The available statistics generally fall into two categories, represented by Fsv and D, respectively. None of them is perfect in measuring population genetic differentiation. Nevertheless, they each have advantages and are valuable for current re- search. In practice, both indices should be calculated and a comparison of them can generate useful insights into the evolutionary processes that influence population differentiation. FsT （GsT） has some unique irreplaceable characteristics assuring its standing as the default measure for the foreseeable near future. Also, it will continue to serve as the standard for any alternative measures to contrast with. Instead of being anxious about making choice between these indices, one should pay due attention to the equili-brium status and the level of diversity （especially Hs） of the populations, since they largely sway the power of a given statistic to address a specific question. We provide a multi-faceted comparative summary of the various statistics, which can serve as a basic reference for readers to guide their applications [Current Zoology 61 （5）： 886-897, 2015].
基金supported by Sino-Africa Joint Research Center(Y323771W07,SAJC201322)the National Natural Science Foundation of China(31300182)
文摘East Africa is a biodiversity hotspot. Haplocarpha rueppelii （Sch.Bip.） Beauverd is mainly distributed in the alpine grassland of East Africa. Here we sampled 65 individuals of eight populations/locations of H. rueppelii including hairy and glabrous forms from Mts. Elgon, Aberdare, Kenya, Kilimanjaro and Bale Mountains. We then sequenced one nuclear and three chloroplast DNA fragments and conducted phylogeographic analyses to test the taxonomic rank of the two forms and causes for the differentiation （intrinsic reproductive isolation and geographic barrier）. The results demonstrate that the species consists of two major groups, one includes the populations from Mts. Elgon, Aberdare and Bale, while the other includes Mts. Kenya and Kilimanjaro. The species has established in Mts. Kenya and Aberdare during the Pleistocene. However, migration rate for individuals between the two mountains was low as showed by gene flow analysis. A barrier for plant dispersal and gene flow would have existed between Mts. Aberdare and Kenya since at least Pleistocene. No change of the taxonomic concept of this species is needed. This study reveals a potential geographic barrier in East Africa. We hope it will arouse more scientists＇ interests in phylogeography and biodiversity of East Africa.
基金Great thanks to Rick Winterbottom for his hard work on improving this manuscript and Abebe Getahun for graciously providing a part of his dissertation. We thank LN Du, MN He, WS Jiang, JH Lan, R Min, B Yang and J Yang for sample collection. GH Cui provided information on collection localities. L Jia and WY Wang helped with laboratory work. GH Yu and YF Huang provided advice on the study. This study was supported by the National Natural Science Foundation of China （30730017, 31201707）, National Basic Research Program of China （2007CB411600, 2008GA001）, Western Light Doctor Programme of Chinese Academy of Sciences, and Yunnan Provincial Science and Technology Program （2009CC008）.
文摘Abstract The Labeoninae is a subfamily of the family Cyprinidae, Order Cypriniformes. Oromandibular morphology within the Labeoninae is the greatest among cyprinid fishes. Although several phylogenetic studies about labeonines have been undertaken the results have been inconsistent and a comprehensive phylogeny is needed. Further, an incongruence between morphological and molecular phylogeny requires a systematic exploration of the significance of morphological characters on the basis of the molecular phylogeny. In this study, a total of 292 nucleotide sequences from 73 individuals （representing 24 genera and 73 species） of Labeoninae were analyzed. The results of the phylogenetic analysis indicate that there are four major clades within Labeoninae and three monophyletic lineages within the fourth clade. Results of the character evolution show that all oromandibular morphological characters are homoplastically distributed on the molecular phylogenetic tree and suggests that these characters evolved several times during the history of labeonines. In particular, the labeonine, a specific disc on the lower lip, has been acquired three times and reversed twice. These morphological characters do not have systematic significance but can be useful for taxonomy. The results of biogeography suggest that the Labeoninae originated from Southeast Asia and separately dispersed to Africa, East Asia and South Asia.
