Geographic variation in evolutionary rescue in a predator-prey system under climate change: an example with aphids and ladybird beetles

Abstract

Under climate change, species can adapt to changing environments through phenotypic plasticity and natural selection, and this kind of evolutionary adaptation can vary geographically. Most species distribution models (SDMs) are built upon the "Niche conservatism" assumption. They often ignore the possibility of "evolutionary rescue" and underestimate species' future range limits under climate change. Here, we select aphids and ladybirds as model species and develop an eco-evolutionary model to explore evolutionary rescue in a predator-prey system under climate change. We model the adaptive change of species thermal performance, accounting for biotic interactions of unique life-history trait. Our results show that there is geographic variation in evolutionary rescue for ladybirds (the predator) across different locations in the United States, with ladybirds being more likely to be rescued from extinction in southeastern locations. The possibility of rescue is primarily influenced by the change in seasonality. Our findings also indicate the additive genetic variance of predators has a stronger influence on the phenotype evolution and population dynamics of both prey and predators, compared to the additive genetic variance of the prey. Our research emphasizes the importance of incorporating evolutionary adaptation when predicting species range shift under climate change. The eco-evolutionary model framework can be applied to study the effect of evolution on interacting species' population abundance and geographic distribution under climate change.