The paradox of energy equivalence
Isaac, Nick J.B.; Storch, David; Carbone, Chris. 2013 The paradox of energy equivalence. Global Ecology and Biogeography, 22 (1). 1-5. 10.1111/j.1466-8238.2012.00782.xBefore downloading, please read NORA policies.
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Energy equivalence, the notion that population energy flux is independent of body mass, has become a key concept in ecology. We argue that energy equivalence is not an ecological ‘rule’, as claimed, but a flawed concept beset by circular reasoning. In fact, the independence of mass and energy flux is a null hypothesis. We show that our mechanistic understanding of size–density relationships (SDRs) follows directly from this null model and the assumption that energy limits abundance. Paradoxically, without this assumption energy equivalence has no meaning and we lack a mechanistic understanding for SDRs. We derive an expression for the strength (r2) of SDRs under the null model, which provides a framework within which to compare published SDRs. This confirms that tight correlations between mass and abundance are a trivial consequence of the span of body masses considered. Our model implies that energy flux varies by five to six orders of magnitude among similarly sized mammals and to a far greater extent in birds. We conclude that the energetic paradigm can be strengthened by considering alternative, non-energetic, hypotheses.
|Item Type:||Publication - Article|
|Digital Object Identifier (DOI):||10.1111/j.1466-8238.2012.00782.x|
|Programmes:||CEH Topics & Objectives 2009 onwards > Biodiversity > BD Topic 2 - Ecological Processes in the Environment|
|Additional Information. Not used in RCUK Gateway to Research.:||This paper is freely available - click on the official URL to access full text|
|Additional Keywords:||abundance, Damuth's rule, ecology, energetics, invariance, macroecology, metabolic scaling, null models, size–density relationship|
|NORA Subject Terms:||Ecology and Environment
Biology and Microbiology
|Date made live:||31 Jul 2012 15:45|
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