Sexual dimorphism and the evolution of seasonal variation in sex allocation in the Hawaii akepa

Author:

Freed, Leonard A., Cann, Rebecca L., Diller, Karl

Title:

Sexual dimorphism and the evolution of seasonal variation in sex allocation in the Hawaii akepa

Periodical:

Evolutionary Ecology Research

Year:

2009

Volume:

11

Pages:

731-757

Subject:

Hawaii Akepa Loxops coccineus

Summary:

This study was done on the endangered Hawaii akepa (Loxops coccineus coccineus), a Hawaiian honeycreeper (Drepanidiane), in an old-growth ohia/koa (Metrosideros polymorphal Acacia koa) forest. The forest is located at the Hakalau Forest National Wildlife Refuge that is on the windward slope of Mauna Kea, on the island of Hawaii. The purpose of this study was to determine: 1) if it is possible to change the sexual dimorphism of fledglings, during different months, to reflect seasonal variation in sex allocation even if these changes are expected, 2) if it is possible for a major shift in the sex ratio of young birds to be attributed to food limitation that affects the seasonal variation in sex allocation, and, 3) to determine how sexual dimorphism is related to seasonal variation in sex allocation. It is based on the hypothesis that the Hawaii akepa females have an advantage of producing male offspring, early in the breeding season, by either increasing the fitness of their sons or by minimizing their own costs of molt-breeding overlap.

Label:

Birds - Akepa

URL:

http://www.evolutionary-ecology.com/sample/eear2347.pdf

Date:

2009

Collection:

Periodicals