Genome Scan to examine extreme hydrogen-sulphide adaptation in Poecilia mexicana. Poecilia mexicana population genomics

Clear water and hydrogen-sulphide adapted populations of the poecilid fish, Poecilia mexicana, were compared to detect molecular signatures of natural selection across the genome. We used the "Pool-Seq" approach: paired-end whole-genome resequencing of genomic DNA pools. Each pool contained a mixture of DNA from more than 100 individuals per population and were sequenced on separate Illumina HiSeq2000 lanes. Four pools were sequenced, representing clear water and sulphide population pairs taken from two geographically isolated river drainages in southern Mexico (Tacotalpa and Puyacatengo).