The collective avoidance of cadmium-contaminated plants by spider mites can have significant implications for the long-term evolution of metal hyperaccumulation as a defense mechanism in plants. This avoidance behavior by herbivores can exert selective pressure on plants, favoring those that are able to hyperaccumulate metals as a defense strategy. Over time, this selective pressure may lead to the prevalence of plant species that have the ability to accumulate high levels of metals, such as cadmium, as a means of deterring herbivory.
Furthermore, the avoidance of cadmium-contaminated plants by spider mites can contribute to the maintenance of metal hyperaccumulation in plant populations. Plants that are successful in deterring herbivores through metal accumulation are likely to have higher fitness and reproductive success, leading to the persistence of this trait in the population. As a result, the evolution of metal hyperaccumulation as a defense mechanism may be reinforced by the collective avoidance behavior of herbivores like spider mites.