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Title: Resolving Food-Web Structure
Food webs are a major focus and organizing theme of ecology, but the data used to assemble them are deficient. Early debates over food-web data focused on taxonomic resolution and completeness, lack of which had produced spurious inferences. Recent data are widely believed to be much better and are used extensively in theoretical and meta-analytic research on network ecology. Confidence in these data rests on the assumptions ( a) that empiricists correctly identified consumers and their foods and ( b) that sampling methods were adequate to detect a near-comprehensive fraction of the trophic interactions between species. Abundant evidence indicates that these assumptions are often invalid, suggesting that most topological food-web data may remain unreliable for inferences about network structure and underlying ecological and evolutionary processes. Morphologically cryptic species are ubiquitous across taxa and regions, and many trophic interactions routinely evade detection by conventional methods. Molecular methods have diagnosed the severity of these problems and are a necessary part of the cure.  more » « less
Award ID(s):
1656527
PAR ID:
10213220
Author(s) / Creator(s):
;
Date Published:
Journal Name:
Annual Review of Ecology, Evolution, and Systematics
Volume:
51
Issue:
1
ISSN:
1543-592X
Page Range / eLocation ID:
55 to 80
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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