Phylogenetic Comparative Methods can Provide Important Insights into the Evolution of Toxic Weaponry

The literature on chemical weaponry of organisms is vast and provides a rich understanding of the composition and mechanisms of the toxins and other components involved. However, an ecological or evolutionary perspective has often been lacking and is largely limited to (1) molecular evolutionary studies of particular toxins (lacking an ecological view); (2) comparisons across different species that ignore phylogenetic relatedness (lacking an evolutionary view); or (3) descriptive studies of venom composition and toxicology that contain post hoc and untested ecological or evolutionary interpretations (a common event but essentially uninformative speculation). Conveniently, comparative biologists have prolifically been developing and using a wide range of phylogenetic comparative methods that allow us to explicitly address many ecological and evolutionary questions relating to venoms and poisons. Nevertheless, these analytical tools and approaches are rarely used and poorly known by biological toxinologists and toxicologists. In this review I aim to (1) introduce phylogenetic comparative methods to the latter audience; (2) highlight the range of questions that can be addressed using them; and (3) encourage biological toxinologists and toxicologists to either seek out adequate training in comparative biology or seek collaboration with comparative biologists to reap the fruits of a powerful interdisciplinary approach to the field.