Are Local Filters Blind to Provenance? Ant Seed Predation Suppresses Exotic Plants More than Natives

The question of whether species' origins influence invasion outcomes has been a point of substantial debate in invasion ecology. Theoretically, colonization outcomes can be predicted based on how species' traits interact with community filters, a process presumably blind to species' o...

Full description

Saved in:
Bibliographic Details
Published in:PloS one Vol. 9; no. 8; p. e103824
Main Authors: Pearson, Dean E., Icasatti, Nadia S., Hierro, Jose L., Bird, Benjamin J.
Format: Journal Article
Language:English
Published: United States Public Library of Science 06.08.2014
Public Library of Science (PLoS)
Subjects:
Agriculture
Animals
Ants
Ants - physiology
Biogeography
Colonization
Communities
Ecology
Ecology and Environmental Sciences
Emergence
Experiments
Feeding Behavior - psychology
Filters
Filtration
Flowers & plants
Impact prediction
Indigenous species
Introduced plants
Introduced Species
Invasive species
Origins
Plant species
Plants
Predation
Predation (Biology)
Preferences
Provenance
Recruitment
Seed predation
Seeds
Success
Canada
Argentina
Montana
United States > US
Colorado
ISSN:1932-6203, 1932-6203
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The question of whether species' origins influence invasion outcomes has been a point of substantial debate in invasion ecology. Theoretically, colonization outcomes can be predicted based on how species' traits interact with community filters, a process presumably blind to species' origins. Yet, exotic plant introductions commonly result in monospecific plant densities not commonly seen in native assemblages, suggesting that exotic species may respond to community filters differently than natives. Here, we tested whether exotic and native species differed in their responses to a local community filter by examining how ant seed predation affected recruitment of eighteen native and exotic plant species in central Argentina. Ant seed predation proved to be an important local filter that strongly suppressed plant recruitment, but ants suppressed exotic recruitment far more than natives (89% of exotic species vs. 22% of natives). Seed size predicted ant impacts on recruitment independent of origins, with ant preference for smaller seeds resulting in smaller seeded plant species being heavily suppressed. The disproportionate effects of provenance arose because exotics had generally smaller seeds than natives. Exotics also exhibited greater emergence and earlier peak emergence than natives in the absence of ants. However, when ants had access to seeds, these potential advantages of exotics were negated due to the filtering bias against exotics. The differences in traits we observed between exotics and natives suggest that higher-order introduction filters or regional processes preselected for certain exotic traits that then interacted with the local seed predation filter. Our results suggest that the interactions between local filters and species traits can predict invasion outcomes, but understanding the role of provenance will require quantifying filtering processes at multiple hierarchical scales and evaluating interactions between filters.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 14
content type line 23
Competing Interests: The authors have declared that no competing interests exist.
Conceived and designed the experiments: DP JH NI. Performed the experiments: NI JH DP. Analyzed the data: BB DP. Contributed reagents/materials/analysis tools: DP BB. Contributed to the writing of the manuscript: DP JH NI BB.
ISSN:1932-6203
1932-6203
DOI:10.1371/journal.pone.0103824