Dispersal and gene flow in free-living marine nematodes

Frontiers in Zoology - Tập 10 - Trang 1-12 - 2013
Sofie Derycke1,2, Thierry Backeljau3,4, Tom Moens1
1Department of Biology, Marine Biology Section, Ghent University, Ghent, Belgium
2CeMoFe, Ghent University, Ghent, Belgium
3Royal Belgian Institute of Natural Sciences (Joint Experimental Molecular Unit), Brussels, Belgium
4Department of Biology, Evolutionary Biology Group, University of Antwerp, Antwerp, Belgium

Tóm tắt

Dispersal and gene flow determine connectivity among populations, and can be studied through population genetics and phylogeography. We here review the results of such a framework for free-living marine nematodes. Although field experiments have illustrated substantial dispersal in nematodes at ecological time scales, analysis of the genetic diversity illustrated the importance of priority effects, founder effects and genetic bottlenecks for population structuring between patches <1 km apart. In contrast, only little genetic structuring was observed within an estuary (<50 km), indicating that these small scale fluctuations in genetic differentiation are stabilized over deeper time scales through extensive gene flow. Interestingly, nematode species with contrasting life histories (extreme colonizers vs persisters) or with different habitat preferences (algae vs sediment) show similar, low genetic structuring. Finally, historical events have shaped the genetic pattern of marine nematodes and show that gene flow is restricted at large geographical scales. We also discuss the presence of substantial cryptic diversity in marine nematodes, and end with highlighting future important steps to further unravel nematode evolution and diversity.

Tài liệu tham khảo

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