Two Degrees of Separation in Complex Food Webs
Feeding relationships can cause invasions, extirpations, and population fluctuations of a species to dramatically affect other species within a variety of natural habitats. Such strong effects rarely propagate through food webs more than three links away from the initial perturbation. However, in large food webs the number of species within these spheres of potential influence are generally unknown. Here we show that the vast majority of species within habitats are three or fewer links from each other. Specifically, food webs from widely different ecosystems are shown to be surprisingly small worlds in which species are only two links from each other on average. Contrary to expectations, species are drawn even closer as network complexity and species richness increase. Our findings are based on seven of the largest and most complex food webs available as well as a food-web model that extends the generality of the empirical results. These results indicate that the dynamics of species within ecosystems may be more highly interconnected and that biodiversity loss and species invasions potentially affect more species than previously thought.
To our knowledge, this item is not available for
download. To find whether it is available, there are three
1. Check below under "Related research" whether another version of this item is available online.
2. Check on the provider's web page whether it is in fact available.
3. Perform a search for a similarly titled item that would be available.
|Date of creation:||Jul 2001|
|Contact details of provider:|| Postal: 1399 Hyde Park Road, Santa Fe, New Mexico 87501|
Web page: http://www.santafe.edu/sfi/publications/working-papers.html
More information through EDIRC
When requesting a correction, please mention this item's handle: RePEc:wop:safiwp:01-07-036. See general information about how to correct material in RePEc.
For technical questions regarding this item, or to correct its authors, title, abstract, bibliographic or download information, contact: (Thomas Krichel)
If references are entirely missing, you can add them using this form.