Oblique color vision in an open-habitat bird: spectral sensitivity, photoreceptor distribution and behavioral implications

作者：Bret A. Moore, Patrice Baumhardt, Megan Doppler, Jacquelyn Randolet, Bradley F. Blackwell, Travis L. DeVault, Ellis R. Loew, Esteban Fernández‐Juricic · 发表于：Journal of Experimental Biology · 年份：2012 · DOI：10.1242/jeb.073957 · 被引用次数：49 · 研究领域：Animal Behavior and Reproduction、Visual perception and processing mechanisms、Neurobiology and Insect Physiology Research

Color vision is not uniform across the retina because of differences in photoreceptor density and distribution. Retinal areas with a high density of cone photoreceptors may overlap with those with a high density of ganglion cells, increasing hue discrimination. However, there are some exceptions to this cell distribution pattern, particularly in species with horizontal visual streaks (bands of high ganglion cell density across the retina) that live in open habitats. We studied the spectral sensitivity and distribution of cone photoreceptors involved in chromatic and achromatic vision in the Canada goose (Branta canadiensis), which possesses an oblique rather than horizontal visual streak at the ganglion cell layer. Using microspectrophotometry, we found that the Canada goose has a violet-sensitive visual system with four visual pigments with absorbance peaks at 409, 458, 509 and 580 nm. The density of most cones involved in chromatic and achromatic vision peaked along a band across the retina that matched the oblique orientation of the visual streak. With the information on visual sensitivity, we calculated chromatic and achromatic contrasts of different goose plumage regions. The regions with the highest visual saliency (cheek, crown, neck and upper tail coverts) were the ones involved in visual displays to maintain flock cohesion. The Canada goose oblique visual streak is the retinal center for chromatic and achromatic vision, allowing individuals to sample the sky and the ...