One of our field sites in the Mojave Desert.
An ash-throated flycatcher in the Mojave Desert. Photo courtesy of Richard Ramirez.
Whiteside Mountain near Highlands, North Carolina
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How does selection favor environmental cues?
Organisms rely upon external cues to avoid detrimental conditions during environmental change. Cues facilitate phenotypic changes by stimulating gene expression to regulate fitness-related traits. In turn, the response helps to avoid conditions that threaten survival. These environmentally-mediated responses are a widespread strategy among organisms termed phenotypic plasticity. My research has shown that temperature is an important cue for developing a desiccation-resistant phenotype. Read more here. How do physiological trade-offs constrain evolution?
Reversible acclimation increases resilience to environmental stress, but acclimation may have hidden costs due to underlying links between related physiological traits. Interactions between physiological traits might result in trade-offs that undermine whole-organism performance and constrain phenotypic evolution. My research has found that trade-offs between water loss and metabolism structures whole-organism strategies for responding to environmental stressors and constrains phenotypic variation. Read more here. How conserved are mechanisms for regulating water loss physiology?
In terrestrial salamanders, gene expression analyses consistently identify regulation of stem cell differentiation and embryonic development of vasculature underlying plasticity in water loss physiology. The temperature-sensitive blood vessel development suggests that salamanders regulate water loss through the regression and regeneration of capillary beds in the skin, indicating that tissue regeneration may be used for physiological purposes beyond replacing lost limbs. My research will focus on understanding these mechanisms further and how conserved they are across amphibians. |