Picture of wind turbine against blue sky

Open Access research with a real impact...

The Strathprints institutional repository is a digital archive of University of Strathclyde research outputs.

The Energy Systems Research Unit (ESRU) within Strathclyde's Department of Mechanical and Aerospace Engineering is producing Open Access research that can help society deploy and optimise renewable energy systems, such as wind turbine technology.

Explore wind turbine research in Strathprints

Explore all of Strathclyde's Open Access research content

The interpretation of tests for ratio-dependence

Ruxton, G.D. and Gurney, William (1992) The interpretation of tests for ratio-dependence. Oikos, 65 (2). pp. 334-335.

Full text not available in this repository. (Request a copy from the Strathclyde author)

Abstract

A number of recent publications have suggested that unstructured consumer-food models, in which the consumer functional response is regarded as a function of the ratio of food and consumer densities, may provide a better guide to the behaviour of natural systems than models in which the functional response is seen as density-independent. Recently, Arditi et al. (1991; Oikos 60: 69-75), have described a series of experiments, which are claimed to demonstrate such ratio-dependence in the functional response of two species of cladocerans. In this letter we re-examine the theory underlying these experiments, and show that although they form a powerful test for density-dependence in the functional response, they do not distinguish ratio-dependence from other equally plausible forms of density dependence. We conclude that the results of Arditi et al.'s experiments may be more effectively interpreted in terms of the density dependent functional response first proposed by J. R. Beddington, and discuss how such experiments might be used to further elucidate the behavioural mechanisms underlying observed density-dependence.