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Updated: Mar 1, 2026

Resurrection of Dormant Daphnia magna: Protocol and Applications

Resurrection of Dormant Daphnia magna: Protocol and Applications

Published on: January 19, 2018

PAEDOMORPHOSIS IN AMBYSTOMA TALPOIDEUM: MAINTENANCE OF POPULATION VARIATION AND ALTERNATIVE LIFE-HISTORY PATHWAYS.

Raymond D Semlitsch¹, Reid N Harris², Henry M Wilbur²

¹Meeman Biological Field Station and Department of Biology, Memphis State University, Memphis, TN, 38152, USA.

Evolution; International Journal of Organic Evolution

|June 1, 2017

Summary

Salamander populations show genetic differences in metamorphosis. While pond drying may drive evolution, some populations exhibit phenotypic plasticity, others a genetic metamorphosis polymorphism.

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Area of Science:

Ecology and Evolutionary Biology
Herpetology
Developmental Biology

Background:

Salamander populations exhibit variation in paedomorphosis and metamorphosis.
Aquatic habitat drying is a potential selective pressure influencing these developmental strategies.

Purpose of the Study:

To investigate if environmental drying regimes are the selective force driving genetic differentiation in metamorphosis propensity in Ambystoma talpoideum.
To test for genetic differentiation in metamorphosis among six natural populations.

Main Methods:

A common garden experiment was conducted using artificial ponds.
Six natural populations of Ambystoma talpoideum were studied under controlled drying regimes.

Main Results:

Evidence supports genetic differentiation in metamorphosis propensity among populations.
Mixed evidence was found for pond-drying regime as the sole selective force.
Some populations demonstrated evolved phenotypic plasticity, while others showed a genetic polymorphism for metamorphosis.

Conclusions:

Genetic factors influence metamorphosis in Ambystoma talpoideum populations.
Environmental drying acts as a selective agent, but other factors may also contribute to the evolution of metamorphosis.
Salamander populations exhibit diverse adaptive strategies, including phenotypic plasticity and genetic polymorphism, in response to environmental cues.