Optimal defense theory defenses predicted

The optimal defense theory predicts that the benefit/cost ratio of defenses will be maximized by natural selection. When a plant consists of different kinds of tissues, within-plant variation in defenses is predicted to depend on the value of the plant part for fitness and on its risk of becoming grazed. The more valuable the tissue is... 

Pavia H, Toth GB, Aberg P (2002) Optimal defense theory elasticity analysis as a tool to predict intraplant variation in defenses. Ecology 83 891-897 Peckol P, Krane JM, Yates JL (1996) Interactive effects of inducible defence and resource availability on pholorotannins in the North Atlantic brown alga Fucus vesiculosus. Mar Ecol Prog Ser 138 209-217... 

The production of toxins is only one aspect of plant defense strategy. As a result of the persistent battle of plants and herbivores, many optimized phenotypes have evolved, such as the preferential accumulation of alkaloids in tissues with a pattern that is consistent with predictions of optimal defense theory,65 i.e., the defense metabolites are allocated preferentially to tissues with a high probability of attack.66 The inducibility of pathways leading to plant secondary compounds as a strategy to minimize the costs of plant defense is a result of permanent optimization. One of a few examples of inducible alkaloid biosynthesis is the different Nicotiana species that exhibit dramatic wound-induced increases of nicotine, nomicotine, or anabasine.67... 

---