Metabolic theory of ecology

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Metabolic rate may relate to organismal temperature and dimensions

Researchers at the Santa Fe Institute, including ecologists James Brown, Brian Enquist, Jamie Gillooly and physicist Geoffrey West, helped to develop the metabolic theory of ecology. This theory predicts a relationship between

metabolic rate and
the body size and temperature of animals, plants, and microbes.

The theory, according to Whitfield, has made evident at least one philosophical divide among scientists. For example, some say complicated phenomena like those in ecology require likewise complicated explanation. Others, presumably including supporters of metabolic ecology, say simpler explanation is not only possible but also preferable.

1 Implications of the theory
2 Alternative to the theory
3 References
4 See also

[edit] Implications of the theory

The theory has two notable implications. Firstly, even a modest rise in the average temperature of Earth's atmosphere and oceans might increase the rate of metabolism of affected organisms. It may also reduce population densities. The reason for this is that if metabolic rate increases, resource consumption might rise, as well. When consumption of a finite set of resources in an environment—in this case, planet Earth—rises, that environment becomes less capable of supporting the same population densities. Secondly, when Earth becomes warmer, pathogens and parasites on the planet may evolve and reproduce more rapidly, making it more difficult for humans and other animals to remain free of disease.

[edit] Alternative to the theory

Jan Kozlowski of the Jagiellonian University is a main developer of an alternative theory that relates metabolic rate to cell dimensions and amount of DNA. But it is unclear if this correlative model can actually account for the patterns covered by the theory of West et al.

Another significant alternative has been proposed by Charles Darveau (Now at University of Ottawa) and colleagues, which postulates that the 0.75 scaling exponent arises as an organismal sum of varying scaling exponents of biochemical and other processes.

[edit] References

Brown, J. H., West, G. B., & B. J. Enquist (2005) Yes, West, Brown and Enquist's model of allometric scaling is both mathematically correct and biologically relevant. Functional Ecology 19:735-738.
Chaui-Berlinck, J. G. (2006) A critical understanding of the fractal model of metabolic scaling. Journal of Experimental Biology 209:3045-3054.
Darveau, C. A., Suarez, R. K., Andrews, R. D., & Hochachka, P. W. (2002) Allometric cascade as a unifying principle of body mass effects on metabolism Nature417:166-170.
Kozlowski, J. & Konarzewski, M. (2004) Is West, Brown and Enquist's model of allometric scaling mathematically correct and biologically relevant? Functional Ecology 18:283-289.
Kozlowski, J. & Konarzewski, M. & Gawelczyk, A. T. (2003) Cell size as a link between noncoding DNA and metabolic rate scaling. Proc Natl Acad Sci U S A 100:14080-14085.
Makarieva, A. M., V. G. Gorshkov, & B. L. Li. (2004) Body size, energy consumption and allometric scaling: a new dimension in the diversity-stability debate. Ecological Complexity 1:139-175.
Makarieva, A. M., V. G. Gorshkov, & B. L. Li. (2005) Revising the distributive networks models of West, Brown and Enquist (1997) and Banavar, Maritan and Rinaldo (1999): Metabolic inequity of living tissues provides clues for the observed allometric scaling rules. Journal of Theoretical Biology 237:291-301.
Makarieva, A. M., V. G. Gorshkov, & B. L. Li. (2005) Biochemical universality of living matter and its metabolic implications. Functional Ecology 19:547-557.
West, G. B., Brown, J. H. & B. J.Enquist (1997) A general model for the origin of allometric scaling laws in biology. Science 276:122-126.
Whitfield, J. (2001) All creatures great and small. Nature 413:342-344.
Whitfield, J. (2004). Ecology's big, hot idea. PLoS Biol 2(12):e440.