The genomic landscape of rapid repeated evolutionary adaptation to toxic pollution in wild fish.
Introduction Environmental pollution is a widespread problem that living organisms have to contend with on a global scale. In contaminated sites especially, wild populations undergo intense selective pressure that may result in phenotypic adaptations to pollutants (Hendry et al., 2008). The scientific article (Reid et al., 2016) discussed in this blogpost explores the genetic mechanisms that have allowed the rapid adaptation to industrial pollutants in wild Atlantic killifish populations. Results The genomic landscape of the killifish populations Atlantic killifish (Fundulus heteroclitus) are non-migratory fish that are abundant along the US east coastline (Fig. 1A). Some killifish populations show inherited resistance to lethal levels of industrial pollutants in sites that have been contaminated for decades. For instance, the authors show that the percentage of larva that survive in increasing concentrations of a highly toxic pollutant called PCB 126, is higher in tolerant populations compared to the sensitive populations (Fig. 1B). To understand the genetic adaptations underlying the rapid adaptation to polluted sites in killifish populations, the authors sequenced the complete genomes from eight populations. Four tolerant populations that reside in highly polluted sites were sampled. Each one was paired with a sensitive population from a nearby site (Fig. 1A). The authors combined …
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