Abstract: Plant defense theories have long been proposed to predict patterns in the expression of defensive strategies against herbivores. Despite convergence and macroevolutionary patterns being an explicit part of defense theories, phylogenetic analyses have not been widely employed to disentangle specific predictions concerning 1) investment in resistance traits, 2) tolerance to damage, and 3) plant growth rate. Using a molecular phylogeny of milkweed I will test some of these predictions and also attempt to unravel some of the multiple evolutionary drivers of plant traits. Consistent with classic coevolutionary theory, the historical pattern of defense evolution in the milkweeds shows an escalating ability to regrow following damage, but declining investment in the two most potent anti-herbivore resistance traits (cardenolides, latex). This pattern implicates specialist herbivores in driving the evolution of tolerance over resistance. Trichomes, however, show a phylogenetic pattern more consistent with this trait being an adaptation to arid environments.