Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/2749
Share/Impact:
Título : Testosterone increases bioavailability of carotenoids: Insights into the honesty of sexual signaling
Autor : Blas, Julio, Pérez-Rodríguez, Lorenzo, Bortolotti, Gary R., Viñuela, Javier, Marchant, Tracy A.
Palabras clave : Honest signaling
Immune function
Immunocompetence handicap hypothesis
Coloration
Carotenoids
Androgens
Sexual selection
Communication
Testosterone
Fecha de publicación : 5-Dec-2006
Editor: National Academy of Sciences (U.S.)
Citación : Blas, J., L. Pérez-Rodríguez, G. Bortolotti, et al. 2006, Testosterone increases bioavailability of carotenoids: Insights into the honesty of sexual signaling. Proceedings of the National Academy of Sciences USA, 103(49), 18633-18637.
Resumen: Androgens and carotenoids play a fundamental role in the expression of secondary sex traits in animals that communicate information on individual quality. In birds, androgens regulate song, aggression, and a variety of sexual ornaments and displays, whereas carotenoids are responsible for the red, yellow, and orange colors of the integument. Parallel, but independent, research lines suggest that the evolutionary stability of each signaling system stems from tradeoffs with immune function: androgens can be immunosuppressive, and carotenoids diverted to coloration prevent their use as immunostimulants. Despite strong similarities in the patterns of sex, age and seasonal variation, social function, and proximate control, there has been little success at integrating potential links between the two signaling systems. These parallel patterns led us to hypothesize that testosterone increases the bioavailability of circulating carotenoids. To test this hypothesis, we manipulated testosterone levels of red-legged partridges Alectoris rufa while monitoring carotenoids, color, and immune function. Testosterone treatment increased the concentration of carotenoids in plasma and liver by >20%. Plasma carotenoids were in turn responsible for individual differences in coloration and immune response. Our results provide experimental evidence for a link between testosterone levels and immunoenhancing carotenoids that (i) reconciles conflicting evidence for the immunosuppressive nature of androgens, (ii) provides physiological grounds for a connection between two of the main signaling systems in animals, (iii) explains how these signaling systems can be evolutionary stable and honest, and (iv) may explain the high prevalence of sexual dimorphism in carotenoid-based coloration in animals.
Versión del editor: http://dx.doi.org/10.1073/pnas.0609189103
URI : http://hdl.handle.net/10261/2749
DOI: 10.1073/pnas.0609189103
Appears in Collections:(EBD) Artículos
(IREC) Artículos

Files in This Item:
File Description SizeFormat 
Blas_PNAS2006 (103)_18633-18637.pdf502,65 kBAdobe PDFView/Open
Show full item record
 
CSIC SFX LinksSFX Query


Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.