Dr. Viraj R. Torsekar’s interview with Bio Patrika hosting “Vigyan Patrika”, a series of author interviews. Dr. Torsekar is currently a Postdoctoral fellow at the Department of Ecology, Evolution, and Behavior in The Hebrew University of Jerusalem, Israel. He completed his PhD from the Centre for Ecological Sciences, Indian Institute of Science, Bangalore under Prof. Rohini Balakrishnan’s supervision. For this paper, he worked with Dr. Maria Thaker on an interesting topic of predator-prey spatial games and published a paper titled “Mate-searching context of prey influences the predator–prey space race” in Proceedings of the Royal Society B journal (2020).
How would you explain your paper’s key results to the non-scientific community?
Predators generally move towards prey in search of a meal. Far from being easy targets, prey proactively avoid predators at multiple spatial scales to reduce risk. But prey cannot focus all their efforts on evading predators since they have other crucial tasks to accomplish, such as foraging and reproduction. In this study, we show how prey’s reproductive behaviour affects their spatial games with predators.
Animals belonging to many taxa search for mates by producing signals and responding to them. These signals allow individuals to form pairs and generally lead to higher mating success. As a part of mate searching behaviour, immobile males signal their availability and location, and mobile females use those signals to localise males and mate with them. Such varying mobility may lead to differential overlap with predators that are tracking prey by eavesdropping on signals and based on the predictability of their locations. Furthermore, given the overlap with predators, individuals might avoid predators differently depending on their mate searching behaviour. We tested these hypotheses in tree crickets that live on short bushes, just like their predators, green lynx spiders, which move within and across bushes to actively hunt.
We quantified the proportion of bushes inhabited by spiders when crickets are present and absent separately for calling males, non-calling males and females. We found that spiders were present in higher proportions when calling males and females are present on the bush, but not for non-calling males. When cricket and spider are experimentally manipulated to co-occur on the same bush, phonotactic females move away from the spider. Surprisingly, males move towards them, potentially as a predator inspection strategy. Hence, we found that individual tree crickets’ sex and mate-seeking behaviour influenced the degree of overlap with predators and their antipredator movement strategies, suggesting that reproductive strategies within a prey species can alter predator-prey space race at multiple spatial scales.
What are the possible consequences of these findings for your research area?
Our work highlights important individual-level differences in prey encounter rates with predators and their antipredator behaviour driven by predators and prey’s ecology and behaviour. Therefore, our results caution against making species-level generalisations regarding predator-prey spatial games. Since we allowed unrestricted movement of both predators and prey and included important controls in experiments involving natural populations, we feel convinced that our results can inform the theory of the fields of predator-prey interactions and mate searching behaviour.
“[…] our results can inform the theory of the fields of predator-prey interactions and mate searching behaviour.”
What was the exciting moment (eureka moment) during your research?
Since this was a multi-scale study with multiple results, there was no one specific eureka moment. But one result which left us equal parts excited and baffled was male crickets moving towards their predators at the fine-scale. It was bizarre and yet, observed in some other prey species.
“[…] one result which left us equal parts excited and baffled was male crickets moving towards their predators at the fine-scale.”
What do you hope to do next?
I’m excited to start research in a field new to me: Ecosystem ecology. This field addresses questions at an ecosystem scale, something I find exciting and I’m looking forward to it.
Where do you seek scientific inspiration?
I seek inspiration from multiple avenues. Primarily, I find conceptually-novel research inspiring and enjoy reading and discussing it. Popular science books on Ecology and Evolution have contributed immensely to drawing me to those fields, e.g., Full House by Stephen Jay Gould. Finally, I find blogs such as Dynamic Ecology both insightful and inspirational.
How do you intend to help Indian science improve?
Currently, my postdoctoral fellowship in Israel restricts my ability to support Indian science. I do my best over Twitter, by communicating interesting research, sharing potential scientific positions and normalising the most under-appreciated part of research: the social aspect of science! But, I intend to return to India and hopefully, in a more permanent role, I wish to contribute towards Indian science in two ways. One is to communicate how fascinating ecological research can be and its importance in the light of fast-changing conditions to non-academic audiences. And secondly, to build international networks to showcase the exciting ecological work being conducted in India, at the global stage.
Torsekar V R*, Thaker M. Mate-searching context of prey influences the predator–prey space race. Proc. Royal Soc. B (2020), 287. DOI: 10.1098/rspb.2020.1462. *Corresponding author.
Risk-Management Ecology Lab
Dept. of Ecology, Evolution, and Behavior
The Hebrew University of Jerusalem, Israel