Data from: Genomic signatures of adaptation in native lizards exposed to human-introduced fire ants

Understanding the process of genetic adaptation in response to
human-mediated ecological change will help elucidate the eco-evolutionary
impacts of human activity. In the 1930s red imported fire ants (Solenopsis
invicta) were accidently introduced to the Southeastern USA, where today
they are both venomous predators and toxic prey to native eastern fence
lizards (Sceloporus undulatus). Here, we investigate potential lizard
adaptation to invasive fire ants by generating whole-genome sequences from
420 lizards across three populations: one with long exposure to fire ants,
and two unexposed populations. Signatures of positive selection exclusive
to the exposed population overlap immune system, growth factor pathways,
and morphological development genes. Among invaded lizards, longer limbs
(used to remove stinging ants) are associated with increased survival. We
identify alleles associated with longer limbs that are highly
differentiated from the unexposed populations, a pattern counter to the
pre-invasion latitudinal cline for limb lengths based on museum specimens.
While we cannot rule out other environmental differences between
populations driving these patterns, these results do constitute plausible
genetic adaptations in lizards invaded by fire ants.