2.2 Molecular methods
DNA was extracted from tissue in accordance with a Chelex 100 method
(Sigma-Aldrich, St Louis, MO). All specimens were genotyped with
genotyping-in-thousand by sequencing method (GT-seq; Campbell et al.,
2015). All samples and loci with ≥ 10% missing genotypes were removed
from further analyses for quality control purposes. Over the period that
these individuals were genotyped, various genetic marker panel updates
occurred, resulting in slight variances of the mix of putatively neutral
and adaptive markers available (Appendix S1 Table S1). Samples were
genotyped with GTseq panels ranging from 368-390 SNPs, and genotype data
were retained when >90% loci successfully genotyped and
had an estimated <0.5% genotyping error based on replicate
genotyping.