Work

Eco‐Evolutionary Feedback to a Pesticide Worsens the Impact of a Pesticide Switch in a Pivotal Freshwater Non‐Target Species

Year: 2026

Type: article

Abstract: Pest management often requires the rotation of insecticides, sequentially exposing non-target populations to different compounds. In a two-phased experiment, we assessed whether exposure to the pesticide chlorpyrifos induces rapid evolution in the non-target species Daphnia magna and quantified the response of control and pre-exposed populations to a second exposure to the same pesticide, another pesticide with the same mode of action (malathion), or a pesticide with another mode of action (deltamethrin). Chlorpyrifos selection induced rapid shifts in genotype composition and reduced genotype richness and strongly influenced population development following the second exposure. Chlorpyrifos-selected populations outperformed control populations when subsequently exposed to chlorpyrifos and malathion but underperformed when exposed to deltamethrin. Our results highlight an eco-evolutionary feedback in which rapid adaptive responses to a pesticide worsen the response when exposed to a different type of pesticide in non-target species, increasing vulnerability to common agricultural practices.

Source: Ecology Letters

DOI: 10.1111/ele.70459