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Vision is the most important sense for birds, since good eyesight is essential for safe flight. Birds have a number of adaptations which give visual acuity superior to that of other vertebrate groups; a pigeon has been described as "two eyes with wings". [ 1] Birds are theropod dinosaurs, [ 2][ 3] and the avian eye resembles that of other ...
Tetrachromacy. The four pigments in a bird's cone cells (in this example, estrildid finches) extend the range of color vision into the ultraviolet. [ 1] Tetrachromacy (from Greek tetra, meaning "four" and chroma, meaning "color") is the condition of possessing four independent channels for conveying color information, or possessing four types ...
Bird, reptilian, and monotreme cone cells. The difference in the signals received from the three cone types allows the brain to perceive a continuous range of colors, through the opponent process of color vision. (Rod cells have a peak sensitivity at 498 nm, roughly halfway between the peak sensitivities of the S and M cones.)
Color vision. Color vision, a feature of visual perception, is an ability to perceive differences between light composed of different frequencies independently of light intensity. Color perception is a part of the larger visual system and is mediated by a complex process between neurons that begins with differential stimulation of different ...
Researchers studying the opsin genes responsible for color-vision pigments have long known that four photopigment opsins exist in birds, reptiles and teleost fish. [3] This indicates that the common ancestor of amphibians and amniotes (≈350 million years ago) had tetrachromatic vision — the ability to see four dimensions of color.
As is the case with many birds of prey, falcons have exceptional powers of vision; the visual acuity of one species has been measured at 2.6 times that of human eyes. [11] They are incredibly fast fliers, with the Peregrine falcons having been recorded diving at speeds of 320 km/h (200 mph), making them the fastest-moving creatures on Earth ...
Avian brain. The avian brain is the central organ of the nervous system in birds. Birds possess large, complex brains, which process, integrate, and coordinate information received from the environment and make decisions on how to respond with the rest of the body. Like in all chordates, the avian brain is contained within the skull bones of ...
List of birds. Penguins. Ostriches. This article lists living orders and families of birds. The links below should then lead to family accounts and hence to individual species. The passerines (perching birds) alone account for well over 5,000 species. In total there are about 10,000 species of birds described worldwide, though one estimate of ...