As Bioindicators
Newts, as with salamanders in general, serve as bioindicators because of their thin, sensitive skin and their presence (or absence) can serve to monitor the health of the environment. Most species are highly sensitive to subtle changes in the pH level of streams and lakes they live in. Because their skin is permeable to water they absorb oxygen and other substances they need through their skin. Scientists will study the stability of the amphibian population when studying the water quality of a particular body of water.
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