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Báo cáo sinh học: "Adaptation by introgression"

Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Adaptation by introgression. | Journal of Biology Minireview Adaptation by introgression Michael L Arnold and Noland H Martin Addresses Department of Genetics University of Georgia Athens Georgia 30602 USA. Department of Biology Texas State University San Marcos TeXas 78666 USA. Correspondence Michael L Arnold. Email arnold@plantbio.uga.edu Abstract Both selective and random processes can affect the outcome of natural hybridization. A recent analysis in BMC Evolutionary Biology of natural hybridization between an introduced and a native salamander reveals the mosaic nature of introgression which is probably caused by a combination of selection and demography. Natural interspecific hybridization has been observed in a diverse array of taxa 1-3 and the production of such hybrids can have a wide range of evolutionary consequences. For instance natural hybridization can act as a destructive force resulting in the fusion of taxa that do not reveal strong reproductive isolation 1 . Alternatively it can result in evolutionary novelty via the production of new reproductively isolated hybrid species 1-3 or by the transfer of potentially adaptive traits through a process known as introgressive hybridization. In a recent article in BMC Evolutionary Biology Fitzpatrick et al. 4 tested for introgressive hybridization by performing a genome-wide scan of native salamander Ambystoma californiense populations and identified genomic regions that have rapidly fixed alternative alleles derived from a recently introduced invasive species Ambystoma mavortium . This rapid assimilation of non-native alleles suggests that selective processes were involved in their fixation. Introgressive hybridization is a multi-step process by which genetic material from one population infiltrates into another genetically differentiated population 5 . In order for introgressive hybridization to take place F1 hybrids must initially be produced between the two species. In nature such hybrid formation is often a rare event owing to the .