PHYLOGENETIC SYSTEMATICS AND BIOMECHANICS IN ECOMORPHOLOGY

Research in all fields of biology increasingly uses phylogenetic syste matics to interpret biological data in an evolutionary context. It is becoming widely accepted that comparative studies of the correlation o f biological features, such as ecomorphological studies, must frame th eir analyses within the context of a phylogenetic hierarchy rather tha n treating each taxonomic unit as an independent replicate. Recent met hods for the interpretation of ecological and functional data in the f ramework of a phylogeny can reveal the degree to which ecomorphologica l characters are correlated with one another, and are congruent with h ierarchical cladistic groups. An example of the ecomorphology of labri d fishes is used here to illustrate the application of several of thes e methods. The structural design and mechanics of the jaws of labrids are tested for ecomorphological associations with the natural diets of these fishes. Methods for analysis of the correlated evolution of bot h discrete and continuous quantitative characters within a phylogeny a re practiced on a single ecomorphological data set. Techniques used in clude character coding, character mapping, phylogenetic autocorrelatio n, independent contrasts, and squared change parsimony. These approach es to diverse biological data allow the study of ecomorphology to acco unt for patterns of phylogenetic ancestry. Biomechanics or functional morphology also plays a vital role in the determination of ecomorpholo gical relationships by clarifying the mechanisms by which morphologies can perform behaviors important to the organism's ecology. The synthe sis of systematics with biomechanics is an example of interdisciplinar y study in which information exchange can elucidate patterns of evolut ion in ecomorphology.