Niche relationships in an assemblage of neotropical granivorous ants.

Persistent Link:
http://hdl.handle.net/10150/186076
Title:
Niche relationships in an assemblage of neotropical granivorous ants.
Author:
Kaspari, Michael Edward.
Issue Date:
1992
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Ants are key players in ecosystem function, especially in the tropics, yet little is known about the diversity and behavior of tropical ant communities. In a lowland wet forest of La Selva, Costa Rica ants are the primary predators of over a third of the sizes of bird-dispersed seeds. Dominated by the tribes Attini, Pheidolini and Solenopsidini, 35-38 species of ant preyed on seeds or seed baits. This is the most diverse granivorous ant community yet recorded, with the high diversity associated with higher population densities, smaller colony sizes and smaller body sizes than North American granivorous ant communities. The size of a frugivore dropping is isometric with the size of the bird producing it, and decreases with rain. Ant predation on these droppings was highly variable in time and space. Discovery and recruitment to droppings increased with dropping size as predicted by simple models. However, partial predation of large droppings produced the highest seed mortality at intermediate-size droppings. Seeds were found in 29% of meter-square samples of ant nests, suggesting seed rain was not highly localized. Small droppings were used by the greatest variety of species--this corresponded to observations of ant aggression at the largest droppings. Niche breadth increased with body size for both seed size and microclimate. Large ants foraged in a greater range of Vapor Pressure Deficits than small ants, as predicted by the law of surface area to volume. Large ants also took a greater variety of seed sizes than small ants, aided through intraspecific size matching in the large species (mostly attines). The tendency for small ant species to have niches nested within those of large ant species highlights the need to understand how body size and colony size influence interactions in ant communities.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Dissertations, Academic.; Entomology.; Ecology.; Ants.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Ecology and Evolutionary Biology; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Rosenzweig, Michael L.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleNiche relationships in an assemblage of neotropical granivorous ants.en_US
dc.creatorKaspari, Michael Edward.en_US
dc.contributor.authorKaspari, Michael Edward.en_US
dc.date.issued1992en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractAnts are key players in ecosystem function, especially in the tropics, yet little is known about the diversity and behavior of tropical ant communities. In a lowland wet forest of La Selva, Costa Rica ants are the primary predators of over a third of the sizes of bird-dispersed seeds. Dominated by the tribes Attini, Pheidolini and Solenopsidini, 35-38 species of ant preyed on seeds or seed baits. This is the most diverse granivorous ant community yet recorded, with the high diversity associated with higher population densities, smaller colony sizes and smaller body sizes than North American granivorous ant communities. The size of a frugivore dropping is isometric with the size of the bird producing it, and decreases with rain. Ant predation on these droppings was highly variable in time and space. Discovery and recruitment to droppings increased with dropping size as predicted by simple models. However, partial predation of large droppings produced the highest seed mortality at intermediate-size droppings. Seeds were found in 29% of meter-square samples of ant nests, suggesting seed rain was not highly localized. Small droppings were used by the greatest variety of species--this corresponded to observations of ant aggression at the largest droppings. Niche breadth increased with body size for both seed size and microclimate. Large ants foraged in a greater range of Vapor Pressure Deficits than small ants, as predicted by the law of surface area to volume. Large ants also took a greater variety of seed sizes than small ants, aided through intraspecific size matching in the large species (mostly attines). The tendency for small ant species to have niches nested within those of large ant species highlights the need to understand how body size and colony size influence interactions in ant communities.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectDissertations, Academic.en_US
dc.subjectEntomology.en_US
dc.subjectEcology.en_US
dc.subjectAnts.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineEcology and Evolutionary Biologyen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairRosenzweig, Michael L.en_US
dc.contributor.committeememberDonoghue, Michael J.en_US
dc.contributor.committeememberVleck, David J.en_US
dc.contributor.committeememberBronstein, Judith L.en_US
dc.contributor.committeememberRussell, Stephen M.en_US
dc.identifier.proquest9309036en_US
dc.identifier.oclc714160190en_US
All Items in UA Campus Repository are protected by copyright, with all rights reserved, unless otherwise indicated.