TY - JOUR
T1 - Spectral sensitivities of photoreceptors and their role in colour discrimination in the green-backed firecrown hummingbird (Sephanoides sephaniodes)
AU - Herrera, Gonzalo
AU - Zagal, Juan Cristóbal
AU - Diaz, Marcelo
AU - Fernández, Maria José
AU - Vielma, Alex
AU - Cure, Michel
AU - Martinez, Jaime
AU - Bozinovic, Francisco
AU - Palacios, Adrián G.
PY - 2008/9
Y1 - 2008/9
N2 - We studied the photopic spectral sensitivity in the green-backed firecrown, Sephanoides sephaniodes, a South American hummingbird, and its possible ecological relationship with preferred flowers and body colouration. Avian colour vision is in general tetrachromatic with at least four types of cones, which vary in sensitivity from the near ultraviolet (UV) to the red wavelength range. Hummingbirds represent an important family of birds, yet little is known about their eye sensitivity, especially about the role of photoreceptors and their oil droplet complements. The photopic electroretinogram shows a main sensitivity peak at 560 nm and a secondary peak in the UV, and may be explained by the presence of four single cones (λmax at ∼370, 440, 508 and 560 nm), and a double cone (λmax at 560 nm) screened by oil droplets. The flowers preferred by the firecrown are those in which the red-green wavelength region predominates and have higher contrast than other flowers. The crown plumage of males is highly iridescent in the red wavelength range (peak at 650 nm) and UV; when plotted in a high-dimensional tetrachromatic space, it falls in a "red + UV" purple hue line, suggesting a potential significant communication signal for sexual differentiation.
AB - We studied the photopic spectral sensitivity in the green-backed firecrown, Sephanoides sephaniodes, a South American hummingbird, and its possible ecological relationship with preferred flowers and body colouration. Avian colour vision is in general tetrachromatic with at least four types of cones, which vary in sensitivity from the near ultraviolet (UV) to the red wavelength range. Hummingbirds represent an important family of birds, yet little is known about their eye sensitivity, especially about the role of photoreceptors and their oil droplet complements. The photopic electroretinogram shows a main sensitivity peak at 560 nm and a secondary peak in the UV, and may be explained by the presence of four single cones (λmax at ∼370, 440, 508 and 560 nm), and a double cone (λmax at 560 nm) screened by oil droplets. The flowers preferred by the firecrown are those in which the red-green wavelength region predominates and have higher contrast than other flowers. The crown plumage of males is highly iridescent in the red wavelength range (peak at 650 nm) and UV; when plotted in a high-dimensional tetrachromatic space, it falls in a "red + UV" purple hue line, suggesting a potential significant communication signal for sexual differentiation.
KW - Electroretinogram
KW - Hummingbird
KW - Neotropical bird
KW - Spectral reflectance
KW - Tetrachromatic vision
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U2 - 10.1007/s00359-008-0349-8
DO - 10.1007/s00359-008-0349-8
M3 - Article
C2 - 18584181
AN - SCOPUS:50249106863
SN - 0340-7594
VL - 194
SP - 785
EP - 794
JO - Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology
JF - Journal of Comparative Physiology A: Neuroethology, Sensory, Neural, and Behavioral Physiology
IS - 9
ER -