Sexually dimorphic melanin-based colour polymorphism, feather melanin content, and wing feather structure in the barn owl (Tyto alba)

Détails

ID Serval
serval:BIB_3A096869784F
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Sexually dimorphic melanin-based colour polymorphism, feather melanin content, and wing feather structure in the barn owl (Tyto alba)
Périodique
Biological Journal of the Linnean Society
Auteur⸱e⸱s
Roulin A., Mangel J., Wakamatsu K., Bachmann T.
ISSN
0024-4066
Statut éditorial
Publié
Date de publication
2013
Peer-reviewed
Oui
Volume
109
Numéro
3
Pages
562-573
Langue
anglais
Résumé
Feathers confer protection against biophysical agents and determine flying ability. The geometry and arrangement of the barbs, together with the keratin and pigments deposited in the feathers, determine the mechanical stability of the vane, and its stiffness and resistance to abrasive agents. In colour-polymorphic species, individuals display alternative colour morphs, which can be associated with different foraging strategies. Each morph may therefore require specific flying abilities, and their feathers may be exposed to different abrasive agents. Feathers of differently coloured individuals may thus have a specific structure, and colour pigments may help resist abrasive agents and improve stiffness. We examined these predictions in the barn owl (Tyto alba), a species for which the ventral body side varies from white to dark reddish pheomelanic, and in the number and size of black spots located at the tip of the feathers. White and reddish birds show different foraging strategies, and the size of black feather spots is associated with several phenotypic attributes. We found that birds displaying a darker reddish coloration on the ventral body side deposit more melanin pigments in their remiges, which also have fewer barbs. This suggests that wear resistance increases with darkness, whereas feathers of lighter coloured birds may bend less easily. Accordingly, individuals displaying a lighter reddish coloration on the ventral body side, and those displaying larger black spots, displayed more black transverse bars on their remiges: as larger-spotted individuals are heavier and longer-winged birds also have more transverse bars, these bars may reduce feather bending when flying. We conclude that differently coloured individuals produce wing feathers of different strengths to adopt alternative behavioural and life history strategies
Mots-clé
abrasion, colour polymorphism, feather, melanin
Web of science
Open Access
Oui
Création de la notice
02/02/2013 16:47
Dernière modification de la notice
20/08/2019 14:29
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