Access

You are not currently logged in.

Access JSTOR through your library or other institution:

login

Log in through your institution.

If You Use a Screen Reader

This content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Journal Article

Competition‐Similarity Relationships and the Nonlinearity of Competitive Effects in Consumer‐Resource Systems

Peter A. Abrams, Claus Rueffler and Russell Dinnage
The American Naturalist
Vol. 172, No. 4 (October 2008), pp. 463-474
DOI: 10.1086/590963
Stable URL: http://www.jstor.org/stable/10.1086/590963
Page Count: 12
Were these topics helpful?
See something inaccurate? Let us know!

Select the topics that are inaccurate.

  • Read Online (Free)
  • Download ($19.00)
  • Subscribe ($19.50)
  • Add to My Lists
  • Cite this Item
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Competition‐Similarity Relationships and the Nonlinearity of Competitive Effects in Consumer‐Resource Systems
Preview not available

Abstract

Abstract: Much previous ecological and evolutionary theory about exploitative competition for a continuous spectrum of resources has used the Lotka‐Volterra model with competition coefficients given by a Gaussian function of niche separation. Using explicit consumer‐resource models, we show that the Lotka‐Volterra model and the assumption of a Gaussian competition‐similarity relationship both fail to reflect the impact of strong resource depletion, which typically reduces the influence of the most heavily used resources on the competitive interaction. Taking proper account of resource depletion reveals that strong exploitative competition between efficient consumers is usually a highly nonlinear interaction, implying that a single measure is no longer sufficient to characterize the process. The nonlinearity usually entails weak coupling of competing species when their abundances are high and equal. Rare invaders are likely to have effects on abundant residents much larger than those of the resident on the invader. Asymmetrical utilization curves often produce asymmetrical competition coefficients. Competition coefficients are typically non‐Gaussian and are often nonmonotonic functions of niche separation. Utilization curve shape and resource growth functions can have major effects on competition‐similarity relationships. A variety of previous theoretical findings need to be reassessed in light of these results.

Page Thumbnails

  • Thumbnail: Page 
1
    1
  • Thumbnail: Page 
2
    2
  • Thumbnail: Page 
3
    3
  • Thumbnail: Page 
4
    4
  • Thumbnail: Page 
5
    5
  • Thumbnail: Page 
6
    6
  • Thumbnail: Page 
7
    7
  • Thumbnail: Page 
8
    8
  • Thumbnail: Page 
9
    9
  • Thumbnail: Page 
10
    10
  • Thumbnail: Page 
11
    11
  • Thumbnail: Page 
12
    12
Part of Sustainability