Evol Ecol Res 9: 789-800 (2007)     Full PDF if your library subscribes.

Protozoan functional responses: effects of species, genotype, and anti-predator defences

Shelly Duquette, Res Altwegg‡ and Bradley R. Anholt*

Department of Biology, University of Victoria, PO Box 3020 Stn CSC, Victoria, BC V8W 3N5, Canada

Author to whom all correspondence should be addressed.
e-mail: banholt@uvic.ca

ABSTRACT

Hypothesis: Induced anti-predator defences reduce foraging efficiency.

Organism: Two clones of Euplotes aediculatus, and one clone of E. plumipes, species of hypotrich ciliated protozoan feeding on the green alga Chlorella vulgaris.

Study site: Laboratory experiment.

Methods: We induced defences using frozen turbellarian flatworm predators. We counted captured cells directly using the autofluorescence of chlorophyll. We then estimated functional responses of induced and uninduced morphs using non-linear mixed effects models of counts of captured cells.

Results: All clones had Type II functional responses. Variation in attack rates and handling times was as large between clones as between species. Only the clone with the largest morphological change clearly had reduced foraging efficiency. This was due to longer handling times.

Keywords: Chorella, chlorophyll autofluorescence, Euplotes, model selection, phenotypic plasticity, Stenostomum.

DOWNLOAD A FREE, FULL PDF COPY
IF you are connected using the IP of a subscribing institution (library, laboratory, etc.)
or through its VPN.

 

        © 2007 Bradley R. Anholt. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.

       Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.

       All copies of abstracts and articles must preserve their copyright notice without modification.