Soft song during aggressive interactions: seasonal changes and endocrine correlates in song sparrows.
Horm Behav
; 62(4): 455-63, 2012 Sep.
Article
en En
| MEDLINE
| ID: mdl-22902893
ABSTRACT
It is well known that songbirds produce high amplitude songs ("broadcast songs"). Songbirds also produce low amplitude songs ("soft songs") during courtship or territorial aggression in the breeding season. Soft songs are important social signals but have been studied far less than broadcast songs. To date, no studies have examined seasonal changes in soft song or its endocrine regulation. Here, in male song sparrows, we examined soft songs during a simulated territorial intrusion in the breeding season and non-breeding season. We also measured plasma testosterone and dehydroepiandrosterone (DHEA) levels in subjects immediately after the aggressive encounter. The total number of songs produced (broadcast+soft songs) did not vary between seasons. However, there was a dramatic increase in the percentage of soft song in the non-breeding season. Further, the percentage of soft song was negatively correlated with plasma testosterone levels in the non-breeding season. There were seasonal differences in the acoustic structure of two major elements of soft song, trills and buzzes. The minimum frequency of trills was lower in the non-breeding season, and the element repetition rate of buzzes was lower in the non-breeding season. To our knowledge, this is the first study to (1) examine soft songs outside of the breeding season and (2) to identify endocrine correlates of soft songs, which are important social signals in songbirds.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Vocalización Animal
/
Agresión
/
Gorriones
Límite:
Animals
Idioma:
En
Revista:
Horm Behav
Año:
2012
Tipo del documento:
Article
País de afiliación:
Canadá