Fig. 4: Population structure and differentiation.

a PCA plot of PC1 and PC2 for nidification species. b PCA plot of PC1 and PC2 for the Nidirana adenopleura complex. c Admixture plot for nidification species with K = 6. d Admixture plot for the N. adenopleura complex with K = 4. e Demographic trajectories for different populations for five nidification species. Nidirana okinavana was not included in this analysis due to a limited sample size. f Demographic trajectories for different populations for seven populations of the N. adenopleura complex. Labels for different populations: N. chapaensis (CP), N. hainanensis (HN), N. yaoica (Y), N. daunchina (D), N. nankunensis (N), N. okinavana (OK), N. mangveni (MV), the Poyang population (PY), N. guangdongensis (GD), and four populations of N. adenopleura: Taiwan (At), north (An), center (Ac), and west (Aw).