Functional Morphology and Physiology: Comparative Methods


A central goal of biology is to compare organismal structure, function and physiology among a diversity of life forms spanning major evolutionary changes. Special methods now allow the integration of physiology, functional morphology and other traits with evolutionary information to reveal physiological evolution.

Keywords: phylogeny; evolution; character change; adaptation; convergence; homoplasy

Figure 1.

Phylogeny of the Vertebrata, showing evolutionary relationships of major vertebrate animal groups.

Figure 2.

Labrid fishes of Pacific coral reefs that show correlated character evolution in the biomechanics of the jaws and the habit of feeding on hard‐shelled or evasive prey. (a) Cheilinus chlorourus, a molluscivore with forceful jaws. (b) Oxycheilinus arenatus, a piscivore with jaws specialized for rapid motion.

Figure 3.

Phylogenetic mapping of the dietary habits and biomechanical characters, using gap‐coded characters. (a) Dietary habits, with red branches for species that feed on evasive prey such as other fishes. (b) Displacement advantage of jaw opening and closing levers, with red branches for species that are specialized for rapid motion of the jaws.


Further Reading

Block BA, Finnerty JR, Stewart AFR and Kidd JA (1993) Evolution of endothermy in fish: mapping physiological traits on a molecular phylogeny. Science 260: 210–213.

Brooks DR and McLennan DA (1991) Phylogeny, Ecology and Behavior: A Research Program in Comparative Biology. Chicago, IL: University of Chicago Press.

Cheverud JM, Dow MM and Leutennegger W (1985) The quantitative assessment of phylogenetic constraints in comparative analyses: sexual dimorphism in body weight among primates. Evolution 39: 1335–1351.

Felsenstein J (1985) Phylogenies and the comparative method. American Naturalist 125: 1–15.

Garland T Jr and Janis CJ (1993) Does metatarsal/femur ratio predict maximal running speed in cursorial mammals? Journal of Zoology (London) 229: 133–151.

Harvey PH and Pagel MD (1991) The Comparative Method in Evolutionary Biology. Oxford: Oxford University Press.

Losos JB (1990) Ecomorphology, performance capability, and scaling of West Indian Anolis lizards: an evolutionary analysis. Ecological Monographs 60: 369–388.

Maddison WP and Maddison DR (1992) MacClade: Analysis of Phylogeny and Character Evolution, Version 3.0. Sunderland, MA: Sinauer Associates.

Martins EP (1996) Phylogenies and the Comparative Method in Animal Behavior. New York: Oxford University Press.

Wainwright PC and Lauder GV (1992) The evolution of feeding biology in sunfishes (Centrarchidae). In: Mayden RW (ed.) Systematics, Historical Ecology, and North American Freshwater Fishes, pp. 472–491. Stanford: Stanford University Press.

Walton BM (1993) Physiology and phylogeny: the evolution of locomotor energetics in hylid frogs. American Naturalist 141: 26–50.

Westneat MW (1995) Feeding, function, and phylogeny: analysis of historical biomechanics and ecology in labrid fishes using comparative methods. Systematic Biology 44: 361–383.

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Westneat, Mark W(Apr 2001) Functional Morphology and Physiology: Comparative Methods. In: eLS. John Wiley & Sons Ltd, Chichester. [doi: 10.1038/npg.els.0001817]