Tunneling Damage Mimicry

Abstract

Insect damage mimicry, especially of tunneling (Fig. 26.2), was the first specific ecological hypothesis that tried to explain the function, evolution and ecology of white leaf variegation. The first to discuss in detail the function of white leaf variegation in the context of possible aposematism was Smith (1986), and while he rejected the aposematic hypothesis for the species (Byttneria aculeata) he studied, he gave a clear and detailed formulation of the aposematic hypothesis for poisonous plants: “The benefits to the plant of chemical defense against herbivores would be greater if herbivores avoided such plants altogether, rather than testing leaves for palatability, and so causing some damage. A distinct leaf color pattern linked with chemical defense might function in this way. Polymorphism for leaf color should then coincide with polymorphisms for chemical defense. Mullerian and Batesian mimicry could result in evolution of similar patterns of variegation, with or without associated toxicity, among other species which have herbivore species in common with the model species”. Smith (1986) found that the variegated morph of B. aculeata was attacked less by herbivorous insects than the non-variegated one.