QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online June 7, 2004
Journal of Experimental Biology 207, 2471-2485 (2004)
Published by The Company of Biologists 2004
doi: 10.1242/jeb.01047

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Siddiqi, A. Articles by Summers, K. Search for Related Content PubMed PubMed Citation Articles by Siddiqi, A. Articles by Summers, K.

Interspecific and intraspecific views of color signals in the strawberry poison frog Dendrobates pumilio

Afsheen Siddiqi¹, Thomas W. Cronin^1,*, Ellis R. Loew², Misha Vorobyev³ and Kyle Summers⁴

¹ Department of Biological Sciences, University of Maryland Baltimore County, Baltimore, MD 21250, USA
² Department of Biomedical Sciences, Cornell University, Ithaca, NY 14853, USA
³ Vision Touch and Hearing Research Centre, University of Queensland, Brisbane, Queensland 4072, Australia
⁴ Department of Biology, East Carolina University, Greenville, NC 27858, USA

^* Author for correspondence (e-mail: cronin{at}umbc.edu)

Accepted 21 April 2004

Poison frogs in the anuran family Dendrobatidae use bright colors on their bodies to advertise toxicity. The species Dendrobates pumilio Schmidt 1858, the strawberry poison frog, shows extreme polymorphism in color and pattern in Panama. It is known that females of D. pumilio preferentially choose mates of their own color morph. Nevertheless, potential predators must clearly see and recognize all color morphs if the aposematic signaling system is to function effectively. We examined the ability of conspecifics and a model predator to discriminate a diverse selection of D. pumilio colors from each other and from background colors. Microspectrophotometry of isolated rod and cone photoreceptors of D. pumilio revealed the presence of a trichromatic photopic visual system. A typical tetrachromatic bird system was used for the model predator. Reflectance spectra of frog and background colors were obtained, and discrimination among spectra in natural illuminants was mathematically modeled. The results revealed that both D. pumilio and the model predator discriminate most colors quite well, both from each other and from typical backgrounds, with the predator generally performing somewhat better than the conspecifics. Each color morph displayed at least one color signal that is highly visible against backgrounds to both visual systems. Our results indicate that the colors displayed by the various color morphs of D. pumilio are effective signals both to conspecifics and to a model predator.

Key words: visual ecology, aposematism, poison frog, Dendrobates pumilio, color vision, color signal