Study sites and sampling
We sampled 13-28 brown anoles from each of 30 populations in southeastern United States from Florida (N = 28 sites) and Georgia (N = 2 sites; Table S1). Sites were organized along three latitudinal transects (Figure S1), completed during three field trips in March-July 2018. Sampling was limited to natural habitats with variable understory light conditions and no evidence of artificial structures. However, we sampled two populations (i.e., LOW and TIF; Table S1) from landscaped vegetation around hotel grounds due to low lizard densities in these areas. In all, we obtained 589 adult males, which were transported to the animal care facility of Harvard University. We kept the lizards for 5-9 weeks in the lab under uniform conditions in individual enclosures (see De Meyer et al., 2019 for a detailed enclosure description), during which time they were measured for a range of related projects. Dewlap characteristics were scored for a subset of 570 lizards at 10-30 days after arrival from the field. All procedures described here for housing and measuring lizards were approved by the Harvard University Institutional Animal Care and Use Committee (IACUC protocol # 26-11).