Meeting Abstract

P1.137  Jan. 4  Phylogenies, adaptation, and the comparative method BUTLER, MA; University of Hawaii at Manoa mbutler@hawaii.edu

I examine evolutionary models for studying evolutionary hypotheses of adaptation using OUCH! “Ornstein-Uhlenbeck for Comparative Hypotheses”. Previously, we developed a direct-modeling approach to study the evolution of a single quantiative character using a phylogenetic tree. We varied the evolutionary model of character evolution to model either drift (pure Brownian Motion) or stabilizing selection towards several distict “optima” which represent diffent “selective regimes”. By allowing researchers to flexibly “paint” alternative combinations of selective regimes on the phylogeny, we can test different hypotheses the tempo and mode of evolution in our focal trait. Here, I present analyses extending the method to two characters using a previously published dataset of archosaur genome size and metabolic rate evolution (Waltari and Edwards 2002).