The Red-Backed Salamander (Plethodon cinereus) is an Effective Model Organism for a Variety of Biological Concepts

Abstract

The red-backed salamander (RBS, Plethodon cinereus) is increasingly recognized as a model organism for a variety of biological subdisciplines, in part due to its ubiquity and abundance throughout northeastern North America (Fisher-Reid et al. 2021). These salamanders can be used for both field- and lab-based work as they are human-tolerant (Arenas et al. 2015). Some of the biological fields using RBS as a model organism include terrestrial ecology, amphibian ecology, evolutionary biology, regeneration, ecotoxicology, and animal behavior (Fisher-Reid et al. 2021). These salamanders are ecologically influential in forest ecosystems, where their biomass in some locations exceeds that of birds during peak breeding season and may be equal to that of all small mammals combined (Burton & Likens 1975). Of the eight most studied salamanders RBS is the only Plethodontid salamander; RBS is an important inclusion considering that more than half of all salamander species are part of the family Plethodontidae and many of the species are declining (Fisher-Reid et al. 2021). Because RBS are highly philopatric and abundant, studies of its population genetics have been used to ask biogeographic questions at a variety of spatial and temporal scale (Fisher-Reid et al. 2013, Cameron et al. 2017). In ecotoxicology, RBS have been used to study how military waste products and pesticides enter and affect terrestrial food webs (Johnson et al. 2004, 2007, 2010; Bazar et al. 2008, 2009, 2010). In animal behavior, RBS has been used to describe changes in territorial behavior based on food availability (Jaeger et al. 2016). Considering that amphibians are the most threatened vertebrate class due anthropogenic changes to their habitat, it is important that more amphibian model organisms are included in research so that we may understand them better with the aim to conserve them. This master’s research and thesis focuses on two ways in which we can use RBS as a model organism. Chapter 1 assesses the efficacy of marking RBS with Visual Implant Elastomer (VIE) for mark-recapture surveys. Understanding and implementing best practices for marking RBS or other small, terrestrial animals, can allow researchers to ask and more effectively test ecological questions which require accurate tracking of individuals over time. Chapter 2 describes how RBS tail regeneration can be impacted by different proportions of their tail being autotomized and the implications for a lengthy wound healing process.