Translator Disclaimer
1 April 2002 PRIMARY SEX-RATIO VARIATION IN TWO BROOD PARASITIC BIRDS: BROWN-HEADED COWBIRD (MOLOTHRUS ATER) AND COMMON CUCKOO (CUCULUS CANORUS)
Author Affiliations +
Abstract

We examined primary sex-ratios of two brood parasitic species, Brown-headed Cowbird (Molothrus ater) and the Common Cuckoo (Cuculus canorus), to determine whether there was any evidence of primary sex-ratio manipulation as has been demonstrated in other species of birds. Despite good reasons for why female brood parasites should manipulate the primary sex-ratio of their young, we found a lack of evidence for a bias in the sex-ratio of eggs produced at the population level, with respect to the host species parasitized or time of breeding season, or in terms of the sex ratio of eggs produced by individual females. Thus, this study provides another example in birds of little evidence for sex-ratio variation in relation to environmental factors.

Michael M. Kasumovic, H. Lisle Gibbs, Bonnie E. Woolfenden, Spencer G. Sealy, and Hiroshi Nakamura "PRIMARY SEX-RATIO VARIATION IN TWO BROOD PARASITIC BIRDS: BROWN-HEADED COWBIRD (MOLOTHRUS ATER) AND COMMON CUCKOO (CUCULUS CANORUS)," The Auk 119(2), 561-566, (1 April 2002). https://doi.org/10.1642/0004-8038(2002)119[0561:PSRVIT]2.0.CO;2
Received: 11 January 2001; Accepted: 8 October 2001; Published: 1 April 2002
JOURNAL ARTICLE
6 PAGES


SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top