Statistical analyses
Significant differences in means between per-species Tajima’s D estimates were tested in R with ‘pairwise.t.test’ in ‘stats’ using the flag ‘p.adjust.method = “fdr”’. Phylogenetic Generalized Least Sqaures (PGLS) was conducted within the ‘phytools’ package (Revell, 2012) with the ‘gls’ and ‘corBrownian’ functions. Phylomorphospace plot was constructed within ‘phytools’ with ‘phylomorphospace’ using default settings. Tests for phylogenetic signal of genome-wide Tajima’s D were conducted with ‘phylosig’ using the flag ‘method = “k”’. Histograms were generated with the function ‘hist’ in the ‘graphics’ package in R. Skewness of distributions was calculated with ‘skewness’ in the ‘e1071’ package (Meyer et al., 2019) in R.