Genetic diversity and Isolation by Distance
The Mantel tests showed a significant correlation between genetic and Euclidean geographic distance (IBD) for all lineages (glm; p<0.05; Suppl. Mat. S1). As Mantel tests are prone to type I error (Wang, 2013) a visual exploration of the data was also done. In general, there was strong IBD, with slope estimates varying from 0.07 to 0.68 (Table 1; Figure 3; Figure S9). However, IBD slopes did not differ significantly across lizard genera, rock-dependent vs. habitat generalists, or in relation to annual mean precipitation (glms; all p>0.05).
Mean individual Ho per lineage varies approximately 30-fold, between 0.007 to 0.192 (Table 1). Except for the slightly positive value for Gehyra gemina , all lineages showed negative Tajima’s D values (-0.058 to -1.376; Table 1) likely reflecting recent population fluctuations. Heteronotia geckos and Carlia amax in the Gulf region of the AMT exhibited the most negative values (Table 1); again, mean Ho was not related aridity, genera or habitat specialization (glm; p>0.05).