title: Herbivore metabolism and stoichiometry each constrain herbivory at different organizational scales across ecosystems.
abstract: Plant-herbivore interactions mediate the trophic structure of ecosystems. We use a comprehensive data set extracted from the literature to test the relative explanatory power of two contrasting bodies of ecological theory, the metabolic theory of ecology (MTE) and ecological stoichiometry (ES), for per-capita and population-level rates of herbivory across ecosystems. We found that ambient temperature and herbivore body size (MTE) as well as stoichiometric mismatch (ES) both constrained herbivory, but at different scales of biological organization. Herbivore body size, which varied over 11 orders of magnitude, was the primary factor explaining variation in per-capita rates of herbivory. Stoichiometric mismatch explained more variation in population-level herbivory rates and also in per-capita rates when we examined data from within functionally similar trophic groups (e.g. zooplankton). Thus, predictions from metabolic and stoichiometric theories offer complementary explanations for patterns of herbivory that operate at different scales of biological organization.
authors.affiliation: Institute for Chemistry and Biology of the Marine Environment, Carl-von-Ossietzky-University Oldenburg, Schleusenstrasse 1, D-26385 Wilhelmshaven, Germany. hillebrand@icbm.de
authors.forename: Helmut
authors.initials: H
authors.lastname: Hillebrand
authors.forename: Elizabeth T
authors.initials: ET
authors.lastname: Borer
authors.forename: Matthew E S
authors.initials: ME
authors.lastname: Bracken
authors.forename: Bradley J
authors.initials: BJ
authors.lastname: Cardinale
authors.forename: Just
authors.initials: J
authors.lastname: Cebrian
authors.forename: Elsa E
authors.initials: EE
authors.lastname: Cleland
authors.forename: James J
authors.initials: JJ
authors.lastname: Elser
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Gruner
authors.forename: W Stanley
authors.initials: WS
authors.lastname: Harpole
authors.forename: Jacqueline T
authors.initials: JT
authors.lastname: Ngai
authors.forename: Stuart
authors.initials: S
authors.lastname: Sandin
authors.forename: Eric W
authors.initials: EW
authors.lastname: Seabloom
authors.forename: Jonathan B
authors.initials: JB
authors.lastname: Shurin
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Smith
authors.forename: Melinda D
authors.initials: MD
authors.lastname: Smith
mesh_terms: D000818:Animals; D049628:Body Size; D001831:Body Temperature; D004435:Eating; D017753:Ecosystem; D004734:Energy Metabolism; D005247:Feeding Behavior; D020387:Food Chain; D007448:Invertebrates / Q000378:metabolism / Q000502:physiology; D008954:Models, Biological; D010788:Photosynthesis; D063245:Plant Development; D010944:Plants / Q000378:metabolism; D011156:Population Density; D011157:Population Dynamics; D015048:Zooplankton / Q000378:metabolism