Model links contaminant-driven animal personality shifts to population instability

Environmental contaminants can alter animal personality in ways that may destabilize ecosystems, according to a data-based predator–prey model reported in Scientific Reports. The researchers found that increasing contaminant concentrations produced a larger proportion of bold rather than shy offspring. In the model, this shift changed predator and prey populations from stable coexistence to periodic dynamics with large oscillations.

The study examined how contaminant-mediated changes in personality could affect predator and prey abundance. Boldness and shyness were represented as distinct phenotypes, while contaminant exposure changed their relative frequency. The central model result was that higher concentrations increased the share of bold phenotypes among offspring, providing a link between developmental alteration of behavior and changes in population trajectories.

That redistribution had a substantial effect within the model. Predator and prey abundances initially showed stable coexistence, but the altered personality composition generated cyclical population dynamics marked by much larger swings. These outputs are model predictions rather than measurements from a field population. They nevertheless demonstrate how changes in an individual-level trait can, when expressed across a population, influence the modeled stability of an ecosystem.

The researchers also added a secondary stressor to represent a multi-stressor environment. This produced a biphasic response in predator populations: a modest increase in boldness improved predator survival, whereas a more drastic increase, consistent with the experimental data used by the model, increased the risk of extinction. The contrast shows that the modeled ecological effect depended on both the magnitude of the personality shift and the addition of another stressor.

Overall, the study indicates that subtle neurophysiological alterations associated with exposure to diverse, common environmental chemicals may have cascading consequences for ecosystem stability. The work is a data-based modeling study connecting contaminant exposure, developmental changes in animal personality and predator–prey dynamics. It does not report a measured collapse in a natural population; instead, it shows how such changes could translate into instability in the model and why the response to a second stressor may be nonlinear.

Subject of Research: Modeling contaminant-driven personality shifts and predator–prey population stability

Article Title: Environmental chemicals cause changes in animal personality that can destabilize populations

Article References: Tierney, K. B., Wang, T. X., Gao, S., Philibert, D. A., Steffler, M., Torwalt, E., Shahriari, A., El-Din, M. G., Lewis, M. A., & Wang, H. (2026). Environmental chemicals cause changes in animal personality that can destabilize populations. Scientific Reports. https://doi.org/10.1038/s41598-026-76089-5

Image Credits: AI Generated

DOI: 10.1038/s41598-026-76089-5

Keywords: environmental contaminants, animal personality, boldness, shyness, predator–prey dynamics, population stability, ecosystem stability, multiple stressors, neurophysiology, data-based modeling, Environmental, chemicals