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Complex population genetic and demographic history of the Salangid, Neosalanx taihuensis, based on cytochrome b sequences.

Zhao L, Zhang J, Liu Z, Funk SM, Wei F, Xu M, Li M - BMC Evol. Biol. (2008)

Bottom Line: This wide ranging distribution makes the species an ideal model for the study of palaeoclimatic effects on population genetic structure and phylogeography.The most common haplotype (H36) was found in 49.15% of all individuals.The observed complex genetic pattern of N. taihuensis is coherent with a scenario of multiple unrelated founding events by long-distance colonization and dispersal combined with contiguous population expansion and locally restricted gene flow.

View Article: PubMed Central - HTML - PubMed

Affiliation: Key laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Chaoyang, Beijing 100101, PR China. zhaoliang@ioz.ac.cn

ABSTRACT

Background: The Salangid icefish Neosalanx taihuensis (Salangidae) is an economically important fish, which is endemic to China, restricted to large freshwater systems (e.g. lakes, large rivers and estuaries) and typically exhibit low vagility. The continuous distribution ranges from the temperate region of the Huai and Yellow River basins to the subtropical region of the Pearl River basin. This wide ranging distribution makes the species an ideal model for the study of palaeoclimatic effects on population genetic structure and phylogeography. Here, we aim to analyze population genetic differentiation within and between river basins and demographic history in order to understand how this species responded to severe climatic oscillations, decline of the sea levels during the Pleistocene ice ages and tectonic activity.

Results: We obtained the complete mtDNA cytochrome b sequences (1141 bp) of 354 individuals from 13 populations in the Pearl River, the Yangze River and the Huai River basin. Thirty-six haplotypes were detected. Haplotype frequency distributions were strongly skewed, with most haplotypes (n = 24) represented only in single samples each and thus restricted to a single population. The most common haplotype (H36) was found in 49.15% of all individuals. Analysis of molecular variance (AMOVA) revealed a random pattern in the distribution of genetic diversity, which is inconsistent with contemporary hydrological structure. Significant levels of genetic subdivision were detected among populations within basins rather than between the three basins. Demographic analysis revealed that the population size in the Pearl River basin has remained relatively constant whereas the populations in the Yangze River and the Huai River basins expanded about 221 and 190 kyr ago, respectively, with the majority of mutations occurring after the last glacial maximum (LGM).

Conclusion: The observed complex genetic pattern of N. taihuensis is coherent with a scenario of multiple unrelated founding events by long-distance colonization and dispersal combined with contiguous population expansion and locally restricted gene flow. We also found that this species was likely severely impacted by past glaciations. More favourable climate and the formation of large suitable habitations together facilitated population expansion after the late Quaternary (especially the LGM). We proposed that all populations should be managed and conserved separately, especially for habitat protection.

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Map of the distribution of N. taihuensis and the sampling locations for this study.
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Figure 1: Map of the distribution of N. taihuensis and the sampling locations for this study.

Mentions: The basins of Yangtze River, Huai River and Pearl River, in which N. taihuensis mainly distributes, are important river systems in China. Although a strong uplifting of the Tibetan plateau occurred during the Pleistocene in southwest China [31], there is no evidence to indicate that large-scale river rearrangement occurred after the Pliocene in the mid-lower reaches of these basins [32]. The Yangze River and the Huai River basin are connected by the Peking Hangzhou Canal, while there are no connection between Pearl River basin and the others[33]. Given the intolerance of the N. taihuensis to waters with some salt content, members of freshwater fish division cannot disperse by river connections [34]. Therefore, we expect vicariance among basins might play an important role in shaping population genetic structure of N. taihuensis. In addition, the glaciations during the Pleistocene, especially the last glacial maximum (LGM) with sea levels lowered (120–140 m below present sea level), should have severely affected the genetic structure of this species. In order to detect the population structure and phylogeographic pattern of N. taihuensis at large geographical scales, samples of N. taihuensis were collected from 13 populations among the Pearl River basin, the Yangtze River basin, and the Huai River basin (Figure. 1). The complete mtDNA cytochrome b gene (cyt b) sequence was used to analyze population genetic differentiation of this species, population dynamics and demographic history, and to show how the glaciations influenced the phylogeographic patterns of freshwater fish, and how this species responded to the severe climatic oscillations and decline of the sea levels during the Pleistocene ice ages.


Complex population genetic and demographic history of the Salangid, Neosalanx taihuensis, based on cytochrome b sequences.

Zhao L, Zhang J, Liu Z, Funk SM, Wei F, Xu M, Li M - BMC Evol. Biol. (2008)

Map of the distribution of N. taihuensis and the sampling locations for this study.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2483725&req=5

Figure 1: Map of the distribution of N. taihuensis and the sampling locations for this study.
Mentions: The basins of Yangtze River, Huai River and Pearl River, in which N. taihuensis mainly distributes, are important river systems in China. Although a strong uplifting of the Tibetan plateau occurred during the Pleistocene in southwest China [31], there is no evidence to indicate that large-scale river rearrangement occurred after the Pliocene in the mid-lower reaches of these basins [32]. The Yangze River and the Huai River basin are connected by the Peking Hangzhou Canal, while there are no connection between Pearl River basin and the others[33]. Given the intolerance of the N. taihuensis to waters with some salt content, members of freshwater fish division cannot disperse by river connections [34]. Therefore, we expect vicariance among basins might play an important role in shaping population genetic structure of N. taihuensis. In addition, the glaciations during the Pleistocene, especially the last glacial maximum (LGM) with sea levels lowered (120–140 m below present sea level), should have severely affected the genetic structure of this species. In order to detect the population structure and phylogeographic pattern of N. taihuensis at large geographical scales, samples of N. taihuensis were collected from 13 populations among the Pearl River basin, the Yangtze River basin, and the Huai River basin (Figure. 1). The complete mtDNA cytochrome b gene (cyt b) sequence was used to analyze population genetic differentiation of this species, population dynamics and demographic history, and to show how the glaciations influenced the phylogeographic patterns of freshwater fish, and how this species responded to the severe climatic oscillations and decline of the sea levels during the Pleistocene ice ages.

Bottom Line: This wide ranging distribution makes the species an ideal model for the study of palaeoclimatic effects on population genetic structure and phylogeography.The most common haplotype (H36) was found in 49.15% of all individuals.The observed complex genetic pattern of N. taihuensis is coherent with a scenario of multiple unrelated founding events by long-distance colonization and dispersal combined with contiguous population expansion and locally restricted gene flow.

View Article: PubMed Central - HTML - PubMed

Affiliation: Key laboratory of Animal Ecology and Conservation Biology, Institute of Zoology, Chinese Academy of Sciences, Chaoyang, Beijing 100101, PR China. zhaoliang@ioz.ac.cn

ABSTRACT

Background: The Salangid icefish Neosalanx taihuensis (Salangidae) is an economically important fish, which is endemic to China, restricted to large freshwater systems (e.g. lakes, large rivers and estuaries) and typically exhibit low vagility. The continuous distribution ranges from the temperate region of the Huai and Yellow River basins to the subtropical region of the Pearl River basin. This wide ranging distribution makes the species an ideal model for the study of palaeoclimatic effects on population genetic structure and phylogeography. Here, we aim to analyze population genetic differentiation within and between river basins and demographic history in order to understand how this species responded to severe climatic oscillations, decline of the sea levels during the Pleistocene ice ages and tectonic activity.

Results: We obtained the complete mtDNA cytochrome b sequences (1141 bp) of 354 individuals from 13 populations in the Pearl River, the Yangze River and the Huai River basin. Thirty-six haplotypes were detected. Haplotype frequency distributions were strongly skewed, with most haplotypes (n = 24) represented only in single samples each and thus restricted to a single population. The most common haplotype (H36) was found in 49.15% of all individuals. Analysis of molecular variance (AMOVA) revealed a random pattern in the distribution of genetic diversity, which is inconsistent with contemporary hydrological structure. Significant levels of genetic subdivision were detected among populations within basins rather than between the three basins. Demographic analysis revealed that the population size in the Pearl River basin has remained relatively constant whereas the populations in the Yangze River and the Huai River basins expanded about 221 and 190 kyr ago, respectively, with the majority of mutations occurring after the last glacial maximum (LGM).

Conclusion: The observed complex genetic pattern of N. taihuensis is coherent with a scenario of multiple unrelated founding events by long-distance colonization and dispersal combined with contiguous population expansion and locally restricted gene flow. We also found that this species was likely severely impacted by past glaciations. More favourable climate and the formation of large suitable habitations together facilitated population expansion after the late Quaternary (especially the LGM). We proposed that all populations should be managed and conserved separately, especially for habitat protection.

Show MeSH
Related in: MedlinePlus