2025 | Comparative Ecology and Evolution of Salamander Life Histories in Temperate and Tropical Environments
FACULTY SEED GRANT | Global Change Center
Comparative ecology and evolution of salamander life histories in temperate and tropical environments
INVESTIGATORS:
- Dr. Holly Kindsvater, Fish and Wildlife Conservation
- Dr. Jen Moss, Biological Sciences
- Dr. Josef Uyeda, Biological Sciences
- Dr. Kevin Hamed, Fish and Wildlife Conservation
As global climate change brings changes to temperature and precipitation patterns, ectothermic (cold-blooded) vertebrates, including salamanders, have been predicted to respond by slowing their growth. This can affect population dynamics, because clutch sizes (birth rates) and death rates decrease with body size. Temperature is commonly assumed to drive ectotherm metabolism and thus growth rates. Temperature also affects resource intake of salamanders by determining when conditions are suitable for foraging for food. However, the role of growing season length has been widely overlooked in studies of growth and demography of ectotherms and has been left out of many climate-envelope models predicting population viability or distributional shifts.
A recent theoretical model predicting energetic allocation to growth and reproduction clarifies that increased growth is evolutionarily advantageous when larger individuals capture more prey and have larger clutches and opportunities to feed and reproduce are restricted in time by harsh conditions. These model predictions need to be validated with studies of ectotherm growth at different elevations and latitudes, where season lengths and temeratures naturally vary. This project will test specific hypotheses from this model using intra- and inter-specific comparisons of plethodontid salamanders.
Plethodontids are the most diverse clade of salamanders with several hundred species, representing over half of salamander biodiversity globally, with dozens of species endemic to the southeastern US alone. They have unusual lungless physiology and long lifespans, and are the dominant vertebrate (in terms of biomass) in eastern forests. This group poses several evolutionary and ecological mysteries: why are there so many plethodontid species, and why are they so abundant relative to other vertebrates? Understanding mechanisms leading to their evolutionary diversification and ecological success is necessary to predict how future climate changes will affect their future population viability.
Each year, the GCC, with funding from the FLSI and the ISCE at Virginia Tech, accepts proposals from GCC faculty to support interdisciplinary research that will lead to collaborative proposals submitted to extramural funding sources. We are seeking projects that link multiple faculty programs and take advantage of unique combinations of expertise at VT, have societal implications and/or a policy component, deal with emerging global change issues that have regional and global significance, and have high potential to eventually leverage external resources.
