Diverging Epigenetic Responses to Wildfire History in Two Sympatric Lizards

Abstract. In altered postdisturbance habitats, sympatric organisms that have different life history strategies may manifest different epigenetic marks in response to changing landscapes. Herein, we explore how DNA methylation patterns change in response to wildfire in two sympatric lizard species with different life histories: Florida Scrub Lizard (Sceloporus woodi) and Six-Lined Racerunner (Aspidocelis sexlineata). Both lizards prefer habitats that have experienced recent wildfire, yet they differ in distribution, body size, life span, reproductive output, vagility, home range size, diet, behavior, and morphology and have different patterns of genetic diversity and differentiation. We used epiRADseq to screen DNA methylation levels in Florida Scrub Lizards (n = 35) and Six-Lined Racerunners (n = 30) from rosemary (Ceratiola ericoides) scrub sites with different time since fire at Archbold Biological Station and Reserve, Florida, USA. We detected seven genomic locations in Florida Scrub Lizards with increased methylation in the site with most recent time since fire compared with individuals from the site with longest time since fire. We failed to detect differential methylation among locations in the Six-Lined Racerunner genome. We also found DNA methylation was positively correlated with time since fire for Florida Scrub Lizards and negatively correlated with time since fire for Six-Lined Racerunners. Our results indicate DNA methylation may play an important role in mediating the response of disturbance-dependent organisms to changing conditions, but the response of methylation to wildfire likely differs among species.