IBD, IBE, and IBR as limits of dispersal
The GDM models including isolation by distance, environment, and
resistance together explained between 24% and 96% of variation in
genetic divergence within lineages. Isolation by Environment (IBE)
alone, or in combination with IBD or IBR, was the most important
predictor of genetic divergence within lineages, while the principal
environmental variables varied across taxa (Table 2). By contrast
neither IBD alone, nor IBR alone, ever explained as much of the
variation in genetic distances as did combined effects. Except for two
lineages (Diporiphora sobria KIM and Gehyra australis ),
climatic variables were included among those contributing strongly to
the models. Geographic distance (always in combination with
environmental variables), was one of the most important variables for 13
of 25 lineages. For the remaining 12 lineages, eight have their genetic
divergence limited by resistance surface, where four are related to
cost-distance SDM; Gehyra australis and G. lapistola to
the presence of a river, Heteronotia binoei NA6 to
evapotranspiration, and D. sobria KIM to slope.