|
|
|
|||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
First published online August 17, 2007
Journal of Experimental Biology 210, 2990-2998 (2007)
Published by The Company of Biologists 2007
doi: 10.1242/jeb.006312
Preferences based on spectral differences in acoustic signals in four species of treefrogs (Anura: Hylidae)
1 Division of Biological Sciences, University of Missouri, Columbia, MO
65211, USA
2 Department of Biology and Health Sciences, Pace University, Pleasantville,
NY 10570, USA
3 Beckman Institute, University of Illinois, Urbana, IL 61801,
USA
4 Department of Biology, James Madison University, MSC 7801, Harrisonburg,
VA 22807, USA
* Author for correspondence (e-mail: gerhardth{at}missouri.edu)
Accepted 26 June 2007
Frogs have two inner ear organs, each tuned to a different range of frequencies. Female treefrogs (Hylidae) of three species in which males produce calls with a bimodal spectrum (Hyla chrysoscelis, H. versicolor, H. arenicolor) preferred alternatives with a bimodal spectrum to alternatives with a single high-frequency peak. By contrast, females of H. avivoca, in which males produce calls with a single, high-frequency peak, preferred synthetic calls with a single high-frequency peak to calls with a bimodal spectrum. These results are consistent with the expectations of the matched-filter hypothesis and run counter to the predictions of the pre-existing bias hypothesis. At moderate to high playback levels (85–90 dB), females of H. avivoca and of two of three mtDNA-defined lineages of H. versicolor preferred unimodal signals with a high-frequency peak to those with a low-frequency peak. Females of H. chrysoscelis, H. arenicolor and the third lineage of H. versicolor did not show a preference, indicating that receiver mechanisms may be at least as evolutionarily labile as call structure. Spectral-peak preferences of gray treefrogs from Missouri, USA were intensity-dependent. Whereas females chose low-frequency calls at 65 dB SPL, there was either no preference (H. chrysoscelis) or a preference for high-frequency calls (H. versicolor) at 85 and 90 dB SPL. These non-linear effects indicate that there is an increasing influence of high-frequency energy on preferences as females approach calling males, and these results serve to emphasize that playback experiments conducted at a single level may have limited generality.
Key words: acoustic communication, matched filtering, pre-existing bias, non-linear effect, Hyla, spectral-structure preference
Related articles in JEB:
This article has been cited by other articles:
![]() |
H. C. Gerhardt Phonotactic selectivity in two cryptic species of gray treefrogs: effects of differences in pulse rate, carrier frequency and playback level J. Exp. Biol., August 15, 2008; 211(16): 2609 - 2616. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Blackburn ONE PEAK OR TWO? J. Exp. Biol., September 1, 2007; 210(17): i - ii. [Full Text] [PDF] |
||||