TY - JOUR
T1 - Interspecific variation in dietary carotenoid assimilation in birds
T2 - Links to phylogeny and color ornamentation
AU - McGraw, Kevin
N1 - Funding Information:
I thank J. Badman and S. Schenone for animal care, O. Crino and P. Nolan for assistance with data collection, and two anonymous referees for constructive comments on the manuscript. The School of Life Sciences and College of Liberal Arts and Sciences at Arizona State University provided financial support for this work. The Institutional Animal Care and Use Committee at Arizona State University (protocol # 05-764R) approved all procedures reported here.
PY - 2005/10
Y1 - 2005/10
N2 - Many birds use carotenoid pigments to acquire rich red, orange, and yellow coloration in feathers and bare parts that is used as a signal of mate quality. Because carotenoids are derived from foods, much attention has been paid to the role of diet in generating color variation both within and among avian species. Less consideration has been given to physiological underpinnings of color variability, especially among species. Here, I surveyed published literature (e.g. captive feeding studies) on carotenoid assimilation in six bird species and completed additional controlled carotenoid-supplementation experiments in two others to consider the ability of different taxa to extract carotenoids from the diet in relation to phylogeny and coloration. I found that, for a given level of carotenoids in the diet, passerine birds (zebra finch, Taeniopygia guttata; house finch, Carpodacus mexicanus; American goldfinch, Carduelis tristis; society finch, Lonchura domestica) exhibit higher levels of carotenoids in circulation than non-passerines like gamebirds (domestic chicken, Gallus domesticus; red junglefowl, Gallus gallus; Japanese quail, Coturnix coturnix; red-legged partridge, Alectoris rufa). This difference in carotenoid accumulation is likely due to interspecific variation in micelle, chylomicron, or lipoprotein concentrations or affinities for xanthophyll carotenoids. Passerine birds more commonly develop carotenoid-based colors than do birds from ancient avian lineages such as Galliformes, and the physiological differences I uncover may explain why songbirds especially capitalize on carotenoid pigments for color production. Ultimately, because we can deconstruct color traits into component biochemical, physical, and physiological parts, avian color signals may serve as a valuable model for illuminating the proximate mechanisms behind interspecific variation in signal use in animals.
AB - Many birds use carotenoid pigments to acquire rich red, orange, and yellow coloration in feathers and bare parts that is used as a signal of mate quality. Because carotenoids are derived from foods, much attention has been paid to the role of diet in generating color variation both within and among avian species. Less consideration has been given to physiological underpinnings of color variability, especially among species. Here, I surveyed published literature (e.g. captive feeding studies) on carotenoid assimilation in six bird species and completed additional controlled carotenoid-supplementation experiments in two others to consider the ability of different taxa to extract carotenoids from the diet in relation to phylogeny and coloration. I found that, for a given level of carotenoids in the diet, passerine birds (zebra finch, Taeniopygia guttata; house finch, Carpodacus mexicanus; American goldfinch, Carduelis tristis; society finch, Lonchura domestica) exhibit higher levels of carotenoids in circulation than non-passerines like gamebirds (domestic chicken, Gallus domesticus; red junglefowl, Gallus gallus; Japanese quail, Coturnix coturnix; red-legged partridge, Alectoris rufa). This difference in carotenoid accumulation is likely due to interspecific variation in micelle, chylomicron, or lipoprotein concentrations or affinities for xanthophyll carotenoids. Passerine birds more commonly develop carotenoid-based colors than do birds from ancient avian lineages such as Galliformes, and the physiological differences I uncover may explain why songbirds especially capitalize on carotenoid pigments for color production. Ultimately, because we can deconstruct color traits into component biochemical, physical, and physiological parts, avian color signals may serve as a valuable model for illuminating the proximate mechanisms behind interspecific variation in signal use in animals.
KW - Carotenoids
KW - Galliformes
KW - House finch
KW - Passeriformes
KW - Plasma carotenoids
KW - Plumage coloration
KW - Sexual selection
KW - Society finch
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U2 - 10.1016/j.cbpb.2005.07.012
DO - 10.1016/j.cbpb.2005.07.012
M3 - Article
C2 - 16129640
AN - SCOPUS:24344473702
SN - 1096-4959
VL - 142
SP - 245
EP - 250
JO - Comparative Biochemistry and Physiology - B Biochemistry and Molecular Biology
JF - Comparative Biochemistry and Physiology - B Biochemistry and Molecular Biology
IS - 2
ER -