Sperm length variation as a predictor of extrapair paternity in passerine birds.

ABSTRACT:

Background

The rate of extrapair paternity is a commonly used index for the risk of sperm competition in birds, but paternity data exist for only a few percent of the approximately 10400 extant species. As paternity analyses require extensive field sampling and costly lab work, species coverage in this field will probably not improve much in the foreseeable future. Recent findings from passerine birds, which constitute the largest avian order (∼5,900 species), suggest that sperm phenotypes carry a signature of sperm competition. Here we examine how well standardized measures of sperm length variation can predict the rate of extrapair paternity in passerine birds.

Methodology/principal findings

We collected sperm samples from 55 passerine species in Canada and Europe for whic

SUBMITTER: Lifjeld JT 

PROVIDER: S-EPMC2956655 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature