Song type variants and aggressive context |
| |
Authors: | W A Searcy S Nowicki C Hogan |
| |
Institution: | (1) Department of Biology, University of Miami, Coral Gables, FL 33124, USA e-mail: wsearcy@miami.edu Tel.: +1-305-2842065, Fax: +1-305-2843039, US;(2) Department of Biology, Duke University, Durham, NC 27708, USA, US;(3) Department of Biology, University of North Carolina, Chapel Hill, NC 27599, USA, US |
| |
Abstract: | We asked whether switching among song type variants functions as a graded signal of aggression in song sparrows (Melospiza melodia). Song type variants are different versions of a given song type and are defined by much smaller acoustic differences than
those defining separate song types. The principal evidence that switching between song types functions as an aggressive signal,
in song sparrows and other species, is that song type switching frequencies increase during aggressive contexts, for example
during simulated territorial intrusions. We tested whether variant switching frequencies change in the same way, using playback
of conspecific song to simulate intrusions. Male song sparrows showed a significant increase in variant switching frequencies
during intrusion relative to before intrusion. After intrusions, variant switching frequencies returned to pre-intrusion levels.
These results are consistent with the hypothesis that variant switching is a graded aggressive signal, but other interpretations
are possible, for example, that variant switching is a signal of submission or represents simple production error.
Received: 20 January 2000 / Revised: 15 July 2000 / Accepted: 30 July 2000 |
| |
Keywords: | Song sparrows Melospiza melodia Song variation |
本文献已被 SpringerLink 等数据库收录! |
|