MATCHING BEHAVIORAL EVOLUTION TO BRAIN MORPHOLOGY

A method is presented to test the relationship between a phylogenetic tree derived from brain morphology, and different hypotheses describin g the evolution of a behavioral trait. This is a question of interest for evolutionary psychologists and behavioral biologists. The paper fi rst discusses how hypotheses for behavioral evolution should be coded for such a comparison, then a triple-permutation test, originally prop osed to compare independently obtained evolutionary trees, is used for the statistical assessment of each hypothesis. Non-parametric correla tion coefficients computed between brain components and appropriately coded behavioral states can then be used to suggest what brain compone nts are responsible for the development of the various states of the b ehavioral trait of interest. The procedure is illustrated with three d ifferent applications relating brain evolution to habitat selection in marsupials, locomotory specialization in primates, and trophic adapta tion in bats.