Eat, Prey, Love
Predators impact prey fitness not just by eating them but also by instilling fear. This fear can influence prey traits that help acquire mates and nutrition—a phenomenon known as non-consumptive effects. Surprisingly, the two broad fitness consequences of responding to predation risk – fewer foraging opportunities and fewer matings – have often been studied separately. However, what animals eat can significantly impact their mating success. This means that by limiting access to nutrition, predators can indirectly influence the reproductive success of their prey.
Understanding this connection is especially important for understanding the expression and success of labile reproductive traits that are nutrient-limited, such as sexual signalling in crickets. In the long term, by integrating the two broad consequences, we aim to unify fields addressing reproductive ecology and nutritional ecology of prey
Phenotype-environment matching in a landscape of fear
Within a single population, individuals exhibit a wide range of phenotypes—just as environments themselves can vary. Remarkably, individuals with certain phenotypes tend to gravitate toward environments that best suit their abilities or performance, driving a phenomenon known as phenotype-environment matching. Do individuals assess their performance across different environments before settling in the one that best suits them? And can assortative mating arise as a result of such habitat choice?
We aim to investigate these causes and consequences of phenotype-environment matching in a heterogeneous environment of risk — where dominant individuals may force competitively weaker conspecifics into riskier habitats. The role of habitat choice in driving adaptive change within populations is an underappreciated mechanism with potentially far-reaching implications. Our long-term goal is to understand whether, and how, organisms can influence their own evolutionary paths through behaviour.
Predator-prey interactions in a rapidly changing world
While the effects of climate change on species abundance and distribution are well studied, its impact on species interactions remains less understood. Our research aims to address this gap by investigating how climate variability—particularly changes in precipitation—modulates both intra- and interspecies interactions. By doing so, we seek mechanistic insights into how ecological relationships will alter under changing climatic conditions.
We focus on arid environments, where precipitation is low on average but highly variable. In dry years, reduced rainfall limits foraging opportunities, constraining both predator and prey populations. These conditions likely decrease predator-prey encounter rates, altering prey perception of predation risk. In contrast, wetter years may create very different risk dynamics. These shifts in perceived risk can, in turn, influence prey mating behaviour, potentially altering mating patterns and driving changes in the frequencies of reproductive traits over time. In the long term, our goal is to understand what maintains stability in prey phenotypes: is it consistent stabilising selection, or does fluctuating selection—driven by climate-linked variation in species interactions—play a larger role?
For a brief idea of Viraj’s past work, please visit the page dedicated to past research