Journal
JOURNAL OF EVOLUTIONARY BIOLOGY
Volume 17, Issue 5, Pages 1111-1120Publisher
WILEY
DOI: 10.1111/j.1420-9101.2004.00743.x
Keywords
sexual selection; indicator; carotenoids; immunocompetence handicap; SRBC; phenotype-linked fertility; sperm velocity; antibody production; spectrometry; ornament colour
Categories
Ask authors/readers for more resources
Female mate choice is often based on exaggerated sexual traits, signals of male qualities that females cannot assess directly. Two such key qualities are male immune and/or sexual competence, whereby honesty in signalling could be maintained by physiological trade-offs. Carotenoid-based ornaments likely constitute such honest signals, as there is direct competition for (limited) carotenoids between ornament deposition and anti-oxidant support of immune or sperm functioning. Using spectrometry, we assessed the potential signalling function of the yellow, carotenoid-based colour of the bill of male mallards, a target of female mate choice. Here we demonstrate that bill reflectance varied with plasma carotenoid level, indicating antioxidant reserves. Moreover, lower relative UV reflectance during autumn pairing predicted immune responsiveness and correlated positively with sperm velocity during breeding, a trait that affects fertility. Our data provide support for current theories that females could use carotenoid-based sexual signals to detect immune vigour and fertilizing ability of prospective mates.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available