Citation

Soma KK, Wingfield JC. Gen. Comp. Endocrinol. 2001; 123(2): 144-155.

Affiliation

Department of Zoology, University of Washington, Seattle, Washington 98195-1800, USA. kiran@physci.ucla.edu

Copyright

(Copyright © 2001, Elsevier Publishing)

DOI

10.1006/gcen.2001.7657

PMID

11482935

Abstract

Many male animals are territorial in the breeding season, when plasma testosterone (T) levels are high, and nonterritorial in the nonbreeding season, when plasma T levels are basal. In contrast to this common pattern, male song sparrows (Melospiza melodia morphna) are territorial year-round, except briefly during molt. Song sparrows are highly aggressive in the nonbreeding season (autumn and winter), even though plasma T, 5 alpha-dihydrotestosterone, androstenedione (AE), and 17beta-estradiol levels are undetectable (

Language: en