Morphological and life-history trait plasticity of two species induced by fish kairomones.

can avoid predation by sensing fish kairomones and producing inducible defenses by altering the phenotype. In this study, the results showed that the morphological and life-history strategies of two species ( and ) exposed to kairomones. In the presence of fish kairomones, the two species exhibited significantly smaller body length at maturity, smaller body length of offspring at the 10th instar, and longer relative tail spine of offspring. Nevertheless, other morphological and life-history traits of the two species differed. showed a significantly longer relative tail spine length and earlier age at maturity after exposure to fish kairomones. The total offspring number of exposed to fish kairomones was significantly higher than that of the control group, whereas that of was significantly lower. These results suggest that the two species have different inducible defense strategies (e.g., morphological and life-history traits) during prolonged exposure to kairomones, and their offspring also develop morphological defenses to avoid predation. It will provide reference for further exploring the adaptive evolution of morphology and life-history traits in the presence of planktivorous fish.