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This content will become publicly available on July 1, 2026

Title: Global Change Asymmetrically Rewires Ecosystems
Global change is complex and multidimensional, making it challenging to understand how human activities affect ecosystem processes. A critical gap in this understanding is how drivers of global change broadly affect food webs. While an industry of studies documents shifts in food webs in response to anthropogenic pressures, a general synthesis is lacking. To address this, we review studies across diverse ecosystems that use stable isotope analysis, energetic food web modelling and gut content analysis to reveal the prevalence of asymmetric rewiring—a phenomenon whereby anthropogenic pressures differentially impact habitats across space, altering some energy pathways within food webs relative to others. We then highlight several examples from the literature to illustrate how this process unfolds. To explore its broader consequences, we use a simple food web model to demonstrate how asymmetric rewiring alters resilience and key ecosystem functions, such as primary and secondary production. Our synthesis uncovers a remarkably general response in food web structure to global change that needs to be better understood to protect nature and the services that human societies rely on in a rapidly changing world.  more » « less
Award ID(s):
2410512
PAR ID:
10628438
Author(s) / Creator(s):
; ; ; ; ; ; ;
Editor(s):
Poisot, Timothée
Publisher / Repository:
Ecology Letters
Date Published:
Journal Name:
Ecology Letters
Volume:
28
Issue:
7
ISSN:
1461-023X
Subject(s) / Keyword(s):
asymmetry ecosystem function food web global change habitat coupling resilience rewiring ecology
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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