Mean mass-specific metabolic rates are strikingly similar across life's major domains: Evidence for life's metabolic optimum
Anastassia M. Makarievaa,b,1, Victor G. Gorshkova,b, Bai-Lian Lib, Steven L. Chownc, Peter B. Reichd, and Valery M. Gavrilove
Author Affiliations
aTheoretical Physics Division, Petersburg Nuclear Physics Institute, Gatchina, St. Petersburg 188300, Russia;
bEcological Complexity and Modelling Laboratory, Department of Botany and Plant Sciences, University of California, Riverside, CA 92521;
cCentre for Invasion Biology, Department of Botany and Zoology, Stellenbosch University, Private Bag X1, Matieland 7602, South Africa;
dDepartment of Forest Resources, University of Minnesota, St. Paul, MN 55108; and
eDepartment of Vertebrate Zoology, Moscow State University, Moscow 119992, Russia
Edited by Stephen W. Pacala, Princeton University, Princeton, NJ, and approved July 24, 2008 (received for review March 3, 2008)
Abstract
A fundamental but unanswered biological question asks how much energy, on average, Earth's different life forms spend per unit mass per unit time to remain alive. Here, using the largest database to date, for 3,006 species that includes most of the range of biological diversity on the planet—from bacteria to elephants, and algae to sapling trees—we show that metabolism displays a striking degree of homeostasis across all of life. We demonstrate that, despite the enormous biochemical, physiological, and ecological differences between the surveyed species that vary over 1020-fold in body mass, mean metabolic rates of major taxonomic groups displayed at physiological rest converge on a narrow range from 0.3 to 9 W kg−1. This 30-fold variation among life's disparate forms represents a remarkably small range compared with the 4,000- to 65,000-fold difference between the mean metabolic rates of the smallest and largest organisms that would be observed if life as a whole conformed to universal quarter-power or third-power allometric scaling laws. The observed broad convergence on a narrow range of basal metabolic rates suggests that organismal designs that fit in this physiological window have been favored by natural selection across all of life's major kingdoms, and that this range might therefore be considered as optimal for living matter as a whole.
allometry body size breathing scaling energy consumption
Footnotes
1To whom correspondence should be addressed. E-mail: elba@peterlink.ru
Author contributions: A.M.M., V.G.G., B.-L.L., S.L.C., P.B.R., and V.M.G. designed research, performed research, analyzed data, and wrote the paper.
The authors declare no conflict of interest.
This article is a PNAS Direct Submission.
This article contains supporting information online at www.pnas.org/cgi/content/full/0802148105/DCSupplemental.
Freely available online through the PNAS open access option.
© 2008 by The National Academy of Sciences of the USA
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PERGUNTA DO BLOGGER:
Se a seleção natural de Darwin, como um dos n mecanismos evolucionários (de A a Z, pois a teoria da evolução é muito plástica e pródiga em mecanismos, se não for X então Y, se não for Y então Z, se não for Z então todo o ABC) é um processo cego, aleatório, não guiado, como é então que os autores afirmaram:
The observed broad convergence on a narrow range of basal metabolic rates suggests that organismal designs that fit in this physiological window have been favored by natural selection across all of life's major kingdoms, and that this range might therefore be considered as optimal for living matter as a whole.Se a seleção natural de Darwin, como um dos n mecanismos evolucionários (de A a Z, pois a teoria da evolução é muito plástica e pródiga em mecanismos, se não for X então Y, se não for Y então Z, se não for Z então todo o ABC) é um processo cego, aleatório, não guiado, como é então que os autores afirmaram:
Se os organismal designs em todos os reinos de vida foram favorecidos pela seleção natural e considerados como optimal para viver, isso não é linguagem teleológica? Parece que sim! É sim! Sendo assim, não é mais evolução darwinista, mas parece muito, é muito Design Inteligente!!!
