Aquatic insect ecophysiological traits reveal phylogenetically based differences in dissolved cadmium susceptibility

Area of Science:

• Evolutionary Biology
• Environmental Toxicology
• Aquatic Entomology

Background:

• Environmental stressors like trace metals pose risks to aquatic ecosystems.
• Understanding insect susceptibility to pollutants requires integrating physiological and evolutionary data.

Purpose of the Study:

• To assess if physiological traits related to cadmium (Cd) susceptibility show patterns of diversity influenced by evolutionary history in aquatic insects.
• To evaluate the utility of a phylogenetically informed approach for studying environmental stress responses.

Main Methods:

• A comparative approach using a species phylogeny for 21 aquatic insect species (Ephemeroptera, Plecoptera, Trichoptera).
• Measurement of physiological traits associated with Cd bioaccumulation, compartmentalization, and susceptibility.
• Quantification of phylogenetic signal for these traits and comparison of regression models.

Main Results:

• All measured traits related to Cd bioaccumulation and susceptibility exhibited significant phylogenetic signal.
• Differences among insect families, rather than functional traits, were key drivers in predictive models.
• A potential tradeoff between Cd elimination and detoxification abilities was observed, especially in mayflies.

Conclusions:

• Physiological responses to Cd are strongly influenced by phylogenetic relatedness in aquatic insects.
• Evolutionary physiology offers a powerful framework for predicting species' responses to environmental stressors.
• Phylogenetic position may serve as a proxy for predicting physiological performance under stress.