Change in Dominance Determines Herbivore Effects on Plant Biodiversity
Document Type
Article
Journal/Book Title/Conference
Nature Ecology & Evolution
Author ORCID Identifier
Sally E. Koerner https://orcid.org/0000-0001-6403-7513
Melinda D. Smith https://orcid.org/0000-0003-4920-6985
Deron E. Burkepile https://orcid.org/0000-0002-0427-0484
Scott L. Collins https://orcid.org/0000-0002-0193-2892
Dave I. Thompson https://orcid.org/0000-0001-9498-8424
Ayana Angassa https://orcid.org/0000-0002-6763-3959
Elisabeth S. Bakker https://orcid.org/0000-0002-5900-9136
Karen H. Beard https://orcid.org/0000-0003-4997-2495
Erik A. Beever https://orcid.org/0000-0002-9369-486X
Elizabeth H. Boughton https://orcid.org/0000-0003-0932-280X
Claire Deleglise https://orcid.org/0000-0001-6119-8311
Tineke Kraaij https://orcid.org/0000-0002-8891-2869
Minna-Maarit Kytöviita https://orcid.org/0000-0002-8928-6951
Alejandro Loydi https://orcid.org/0000-0002-0306-905X
Suzanne Jane Milton https://orcid.org/0000-0003-4390-6040
Todd M. Palmer https://orcid.org/0000-0001-5710-9750
Salvador Rebollo https://orcid.org/0000-0001-8797-1122
Corinna Riginos https://orcid.org/0000-0001-9082-5206
Anita C. Risch https://orcid.org/0000-0003-0531-8336
Kathryn A. Schoenecker https://orcid.org/0000-0001-9906-911X
Nick L. Schultz https://orcid.org/0000-0002-6760-9481
Frances Siebert https://orcid.org/0000-0001-5549-8211
Karen A. Stahlheber https://orcid.org/0000-0003-4271-6878
Martijn L. Vandegehuchte https://orcid.org/0000-0003-1283-4654
Jianshuang Wu https://orcid.org/0000-0002-6768-8255
Truman P. Young https://orcid.org/0000-0002-7326-3894
Volume
2
Publisher
Nature Publishing Group
Publication Date
10-29-2018
First Page
1925
Last Page
1932
Abstract
Herbivores alter plant biodiversity (species richness) in many of the world's ecosystems, but the magnitude and the direction of herbivore effects on biodiversity vary widely within and among ecosystems. One current theory predicts that herbivores enhance plant biodiversity at high productivity but have the opposite effect at low productivity. Yet, empirical support for the importance of site productivity as a mediator of these herbivore impacts is equivocal. Here, we synthesize data from 252 large-herbivore exclusion studies, spanning a 20-fold range in site productivity, to test an alternative hypothesis–that herbivore-induced changes in the competitive environment determine the response of plant biodiversity to herbivory irrespective of productivity. Under this hypothesis, when herbivores reduce the abundance (biomass, cover) of dominant species (for example, because the dominant plant is palatable), additional resources become available to support new species, thereby increasing biodiversity. By contrast, if herbivores promote high dominance by increasing the abundance of herbivory-resistant, unpalatable species, then resource availability for other species decreases reducing biodiversity. We show that herbivore-induced change in dominance, independent of site productivity or precipitation (a proxy for productivity), is the best predictor of herbivore effects on biodiversity in grassland and savannah sites. Given that most herbaceous ecosystems are dominated by one or a few species, altering the competitive environment via herbivores or by other means may be an effective strategy for conserving biodiversity in grasslands and savannahs globally.
Recommended Citation
Koerner, S.E., Smith, M.D., Burkepile, D.E. et al. Change in dominance determines herbivore effects on plant biodiversity. Nat Ecol Evol 2, 1925–1932 (2018). https://doi.org/10.1038/s41559-018-0696-y
