Morphological selection in a foundered population of lizards (Salvator merianae; Teiidae) in a novel environment in the southeastern United States

Newlin, Ezekiel

Allert, Evan

Pikstein, Rachel

Department of Biology

Grand Canyon University

Phoenix, Arizona USA

rpbiologist@gmail.com

Introduced herpetofauna offer remarkable opportunities to assess short-time speciation in vertebrate ectotherms. Additionally, such evaluation can demonstrate ecosystem structural changes, through studying growth and reproduction rates in species who utilize sudden diverse adaptation scenarios. Our 9-year study sampled twelve morphological variables on two species of tegu lizard, in addition to collecting blood for genome and mitochondrial sequencing. Comparisons were made between captive and invasive specimens, as well as between species parameters. Sampled animals demonstrated remarkable diversity in coloration, banding pattern, body size, jowl development in males and females, and skull dimensions; as well as behavioral range from docile to aggressive. A greater diversity and genetic robustness were observed among captive-bred animals; S. merianae already exhibits a remarkable spectrum of adaptive characteristics; from cold tolerance, to dietary preferences, to habitat choice. A true omnivore with molar dentation reflective of similar niche mammals, functioning as an opportunistic consumer. The presence of hybridization within this invasive species, if found, could further aid in phenotypic plasticity, increasing colonization success. Results aim to further uncover the nuisances of invasion establishment in squamates, as well as to better assess the genetic diversity and conservation needs within the genus Salvator.