Research Training Program

Smithsonian Institution
National Museum of Natural History

PROJECT SUMMARY
1997

Anna M. Munoz
New Mexico State University
Las Cruces, NM
W. Ronald Heyer, Ph.D.
Supervising Scientist
Department of Vertebrate Zoology
Division of Reptiles and Amphibians
"The opportunity to work at the Smithsonian with some of the leaders in my field has been an experience I shall never forget. The programs and opportunities provided through this internship have helped me to grow personally and professionally. The time I have spent here has undoubtedly been a major turning point in my career. "

Comparison of Advertisement Calls for Two Populations of Eleutherodactylus fenestratus

ABSTRACT
Advertisement calls play an important role in the reproductive behavior of anurans. Males produce advertisement calls to attract females and define territories. Several studies have shown that female anurans are able to distinguish calls produced by members of the same species from those of other species, making advertisement calls a species isolating mechanism among anurans. Discrimination of calls by females is based on the temporal and spectral characteristics of the call. Temporal characteristics consist of the call duration, call repetition rate, the number of notes per call, note duration, and note pulsation. Spectral characteristics describe the frequency and harmonic structure of the call. It has been stated that although spectral characteristics are important for call recognition, temporal characteristics are the primary mechanism for species discrimination. Researchers sometimes use calls to identify anuran species in the field. In the lab, recordings of calls are used to identify species as well as gain insight on natural history traits pertaining to behavior, vocalization and hearing. This study consisted of analyzing cassette recordings of advertisement calls for two populations of Eleutherodactylus fenestratus; one from Tambopata, Peru and the other from Chapada dos Guimarães, Brazil, to show that the two populations represent distinct species. These findings were based on differences in the temporal structure of the calls.

This research was supported by a grant from the National Science Foundation Research Experiences for Undergraduates program, Award Number DBI-9531331.

Letter of Gratitude