White tail plumage and brood sex ratio in dark-eyed juncos (<Emphasis Type="BoldItalic">Junco hyemalis thurberi</Emphasis>) |
| |
Authors: | Elise D Ferree |
| |
Institution: | (1) Department of Ecology and Evolutionary Biology, University of California, Santa Cruz, CA 95064, USA;(2) Lab of Ornithology, Cornell University, 159 Sapsucker Woods Road, Ithaca, NY 14850, USA |
| |
Abstract: | Theory, empirical examples, and recently, proximate mechanisms point to the possibility of adaptive sex ratio adjustment in
various organisms. General predictions state that a female should adjust her offspring sex ratio to maximize the benefits
or minimize the costs of reproduction given her physical condition or current social and environmental conditions. I tested
for an influence of male attractiveness on brood sex ratio in a population of dark-eyed juncos (Junco hyemalis thurberi) by manipulating a male’s white outer tail feathers (“tail white”). Experimentally increasing male tail white did not significantly
affect sex ratio, nor was premanipulated male tail white significantly related to brood sex ratio. However, the amount of
white on the female’s outer tail feathers, independently of female condition, was positively related to the number of sons
in a brood. Determining how a female’s potential genetic contribution to her sons’ attractiveness influences offspring sex
ratio should be a priority for future research. |
| |
Keywords: | Differential allocation Sex ratio Maternal effects Dark-eyed junco |
本文献已被 SpringerLink 等数据库收录! |
|