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Morphological Polymorphism Associated with Alternative Reproductive Tactics in a Plethodontid Salamander
The American Naturalist
|March 27, 2019
Summary
Alternative reproductive tactics (ARTs) in salamanders show distinct male behaviors and morphology. Environmental differences maintain these ARTs, influencing reproductive success and variation in the two-lined salamander species complex.
Area of Science:
- Evolutionary biology
- Ecology
- Behavioral ecology
Background:
- Polymorphism and alternative reproductive tactics (ARTs) are key to understanding evolutionary variation.
- ARTs can be maintained by environmental heterogeneity and distinct reproductive niches, not just social parasitism.
Purpose of the Study:
- To investigate the role of environmental heterogeneity in maintaining ARTs in plethodontid salamanders.
- To demonstrate a specific example of ARTs in the two-lined salamander (Eurycea bislineata) species complex.
Main Methods:
- Genomic analysis
- Behavioral observations
- Karyological studies
- Field data collection
Main Results:
- Identified two distinct ARTs in male salamanders: "searching" and "guarding."
- These tactics are linked to different reproductive niches and exhibit significant, inflexible morphological differences.
- Evidence suggests ARTs exist within the Eurycea bislineata complex, with some related species fixed for a single tactic.
Conclusions:
- Environmental heterogeneity is a significant factor in maintaining behavioral and morphological variation through ARTs in salamanders.
- The two-lined salamander species complex provides a model system for studying the evolution of ARTs and their relationship with parental care.
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