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bioRxiv · 10.1101/2022.09.13.507786

Socially transmitted innovations in dynamic predator-prey systems

Abstract

Individual behavioral variation is common, yet often we do not know how it is maintained. A potential explanation is that some behaviors must be acquired rather than genetically inherited. We investigate the social transmission of behavioral innovations, which can be key for the success of predator species, especially in contexts where environmental changes take place. We examine innovation in two classic predator-prey models. We assume that innovations increase predator attack rates or conversion efficiencies, or that innovations reduce predator mortality or prey handling time. We find that a common outcome of innovations is the destabilization of the system. Destabilizing effects include increasing oscillations or limit cycles. If either of these outcomes increases the risk of extinction, innovations that benefit individual predators may not have positive long-term effects on predator populations. Furthermore, as populations cycle, innovative individuals can be nearly eliminated, maintaining temporal behavioral variability. The destabilizing effects of behavioral innovations on predator-prey dynamics could have implications for biological invasions, urban populations, endangered species, and, more broadly, the maintenance of behavioral polymorphisms.

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BibTeXRIS

Kikuchi, D. W., Simon, M. W.. 2022-09-15. Socially transmitted innovations in dynamic predator-prey systems. https://doi.org/10.1101/2022.09.13.507786

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