Semester of Graduation
Summer 2025
Degree
Master of Science (MS)
Department
Biological Sciences
Document Type
Thesis
Abstract
Characterizing niche differences in closely related species can provide valuable insights into the extent of ecological divergence between species, and the potential evolutionary processes behind speciation. This study builds the first ecological niche models for the Eurycea dwarf salamander species complex, which includes five species with varying distributions across the southeastern United States. Ecological niche models (ENMs) were built for each species using the machine-learning algorithm, MaxEnt. We used pairwise niche overlap analyses and statistical validation techniques to investigate potential ecological drivers behind species divergence and the degree of niche overlap among the five Eurycea species. We found an overall pattern of niche divergence among this species group, with our results showing significant niche differentiation in eight out of ten pairwise comparisons. Climatic variables, particularly temperature-related metrics, were found to play a significant role in shaping species distributions but contributions varied across species. Our results provide support for the previously suggested adaptive radiation of Eurycea species in the southeast US, highlighting the importance of ecological factors in diversification. Further, our ENM results suggest novel areas for future field investigations and conservation efforts of these species.
Date
5-30-2025
Recommended Citation
Roy, Sarah, "ASSESSING NICHE DIFFERENCES ACROSS THE DWARF SALAMANDER SPECIES COMPLEX OF THE SOUTHEAST US" (2025). LSU Master's Theses. 6171.
https://repository.lsu.edu/gradschool_theses/6171
Committee Chair
James Cronin