Phylogenetic constraints and adaptation explain food-web structure.
Food webs are descriptions of who eats whom in an ecosystem. Although extremely complex and variable, their structure possesses basic regularities. A fascinating question is to find a simple model capturing the underlying processes behind these repeatable patterns. Until now, two models have been devised for the description of trophic interactions within a natural community. Both are essentially based on the concept of ecological niche, with the consumers organized along a single niche dimension; for example, prey size. Unfortunately, they fail to describe adequately recent and high-quality data. Here, we propose a new model built on the hypothesis that any species' diet is the consequence of phylogenetic constraints and adaptation. Simple rules incorporating both concepts yield food webs whose structure is very close to real data. Consumers are organized in groups forming a nested hierarchy, which better reflects the complexity and multidimensionality of most natural systems.
Institut de Zoologie, University of Neuchâtel, Rue Emile-Argand 11, CP2, CH-2007 Neuchâtel, Switzerland.
Marie-France
MF
Cattin
Louis-Félix
LF
Bersier
Carolin
C
Banasek-Richter
Richard
R
Baltensperger
Jean-Pierre
JP
Gabriel
D000222:Adaptation, Physiological; D000818:Animals; D004032:Diet; D020387:Food Chain; D005518:Food Preferences; D005843:Geography; D008954:Models, Biological; D010802:Phylogeny; D011235:Predatory Behavior; D013045:Species Specificity