My research is focused on understanding the evolution and ecology of inducible defenses, phenotypic traits whose expression is modified by the presence of predators. Such phenotypic plasticity is widespread in the natural world, with most organisms capable of modifying some aspect of their phenotype to reduce the risk of predation. My research investigates three aspects of these defenses that are both conceptually challenging and fundamental to understanding the biological implications of inducible defense.

• Optimal defense expression: Basic theory on the evolution of inducible defenses suggests that defense expression must carry a fitness cost to the individual, else the defenses would be expressed constituitively. This cost-benefit tradeoff makes determining optimal defense expression a non-trivial problem, with solutions that depend upon the details of how costs and benefits are manifested. My own research into this problem has generated novel predictions regarding the evolution of qualitatively different defense strategies, including strategies that invest in multiple defenses.

• Ecological consequences of inducible defense: Inducible defenses alter the interactions between species, often in unexpected ways. In particular, inducible defenses dynamically link species through their traits. This implies a fundamental difference with basic ecological theory that treats traits as fixed and links species only through their densities (e.g., a predator consuming prey). I have shown that induced trait changes can dramatically alter the structure and interactions in multi-species ecological communities, even in the absense of direct changes in species' densities.

• Predictive modeling of ecological systems: Existing theory suggests that these two areas of research are fundamentally linked: the details of inducible defense costs and benefits are critical for determining the ecological effects of these defenses. Unfortunately, these cost-benefit tradeoffs have proven impossible to empirically measure, limiting the broader acceptance and application of ecological models of inducible defense. By confronting models for trait expression with empirical data, recently developed statistical fitting tools can estimate these tradeoff shapes directly, allowing for predictive modeling of the effects of inducible defense in ecological communities.

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