NSF Postdoctoral Fellowship in Biology FY 2021: Parallel evolution of lizards in urban heat islands: locomotor performance, muscle physiology, and gene regulation

Rummel, Andrea, Providence RI

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2021, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the Fellow that will contribute to the area of Rules of Life in innovative ways. Temperature has a pervasive effect on animal performance and are of concern for both wildlife and humans. Because urban areas tend to be hotter than rural areas, a phenomenon known as the urban heat island effect, cities provide an opportunity to study how animals acclimate and adapt to high temperatures. This research explores adaptation to high temperatures in crested anole lizards living in cities relative to lizards living in forests in Puerto Rico through the lens of the locomotor system. The Fellow will compare the relationship to temperature of running speeds and muscle performance in city and forest lizards, and then examine genetic changes which underlie differences in responses to temperature. This research will deepen our understanding of how animals respond and adapt to the increasing temperatures predicted during climate change. The Fellow will also develop educational materials for K-12 students and incarcerated students as well as mentoring undergraduates. This project associates morphological, locomotor, and physiological phenotypes with features of the crested anole transcriptome to test the hypothesis that adaptive modification of fine-scale muscle physiology underlies divergence in the thermal tolerance of locomotor performance. The study system consists of multiple, independently derived urban and forest populations of crested anole lizards in Puerto Rico. Locomotor performance will be assessed by measuring sprint speeds across a range of temperatures, as well as morphological variables that are known to influence sprint speed in lizards. To disentangle the contributions of morphological and physiological subordinate traits to whole animal performance, the Fellow will then measure the intrinsic contractile properties of the locomotor muscles powering sprinting across temperatures to assess the impact of muscle thermal sensitivity on locomotor performance. Finally, muscle transcriptomes will be compared between urban–forest pairs and across localities to identify differentially expressed genes and signatures of selection which are associated with differences in temperature-dependent performance. This work will significantly expand our current knowledge of how urban environments modify complex phenotypes on rapid timescales. Under the guidance of Dr. Campbell-Staton, the Fellow will receive training in thermal physiology and transcriptomics, and enhance mentorship and communication skills by working with undergraduates and other students. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.