Food webs are representations of who-eats-whom in ecological communities. Food web structure has been studied during decades in the belief that structure greatly determines community dynamics. While empirical studies have described aggregate statistical measures of many-species food webs, theoretical studies have explored the dynamic properties of simple trophic modules such as tri-trophic food chains. I will review recent work aimed at bridging between these two independent research agendas by exploring the relative frequency of different trophic modules in highly resolved food webs. This research has benefited from parallel work on patterns of interconnections overrepresented in complex networks (i.e., network motifs). I will follow by extending these results to considering quantitative trophic modules. Interaction strengths between species are combined non-randomly to form the basic construction blocks of food-webs. These interaction strength motifs are essential for understanding how ecological communities are organized and how they respond to human exploitation.
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Bascompte, J., and C.J. Melián. 2005. Simple trophic modules for complex food webs. Ecology 86: 2868-2873.
Bascompte, J., C.J. Melián, and E. Sala. 2005. Interaction strength combinations and the overfishing of a marine food web. Proc. Natl. Acad. Sci. USA 102: 5443-5447