Fig. 2

Sampling altitude and selective sweep analysis of different high-altitude adaptations of the Mongolian racerunner. a Geographic distribution of the six representative populations. The altitude (m) of the sampling sites in this study is visualized. b Neighbor-joining tree constructed from the allele sharing matrix of variants of 61 Mongolian racerunner individuals. The orientations approximately fit the sample geographic locations. The reliability of the neighbor-joining tree was estimated using 100 bootstrap pseudo-replicates. c–e The panels show the distribution of log₂(θ_π ratios) and F_ST values that were calculated in 40-kb windows and 20-kb steps in mid- and high-altitude populations compared with low-altitude populations. The points in red (corresponding to the top 1% of the log₂(θ_π ratios) distribution and the top 1% of the F_ST value distribution) are genomic regions identified to be under selection in one mid-altitude population (NeiMonggol (NMG, ~ 1000 m)), and two high-altitude populations (GanSu (GS, ~ 2000 m), and Qinghai (QH, ~ 2600 m)). The ~ 1000 m (NMG) population was compared with three low populations (HB, HEB, and HN: altitude under ~ 300 m), the ~ 2000 m (GS) population was compared with three low populations and the NMG population, and the ~ 2600 m (QH) population compared with three low populations, the NMG population, and the GS population. The genes in red functioned by responding to hypoxia or UV, which are important for high-altitude adaptation in lizards. The PHF14 gene was verified by cell experiments. The explanation of other highlighted genes were shown in Fig. 3 legend. f–h The panels show the GO enrichment results (P < 0.05 by Fisher exact test) of NMG, GS, and QH positively selected genes. The sizes of the circles represent the number of genes