Search results
Results From The WOW.Com Content Network
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 ...
Albinism is the congenital absence of melanin in an animal or plant resulting in white hair, feathers, scales and skin and reddish pink or blue eyes. [ 1][ 2] Individuals with the condition are referred to as albinos . Varied use and interpretation of the terms mean that written reports of albinistic animals can be difficult to verify.
Blindness in animals. Visual perception in animals plays an important role in the animal kingdom, most importantly for the identification of food sources and avoidance of predators. For this reason, blindness in animals is a unique topic of study. In general, nocturnal or subterranean animals have less interest in the visual world, and depend ...
Monocular vision vision is known as seeing and using only one eye in the human species. Depth perception in monocular vision is reduced compared to binocular vision, but still is active primarily due to accommodation of the eye and motion parallax. The word monocular comes from the Greek root, mono for single, and the Latin root, oculus for eye.
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 ...
Pionites melanocephalus. Pionites leucogaster. Pionites xanthomerius [ 1] Pionites xanthurus [ 1] Ranges of black-headed parrot (green) and white-bellied parrot complex overlap. Caique ( / kaɪˈiːk / or / kɑːˈiːk / [ 3]) refers to a group of four species of parrots in the genus Pionites endemic to the Amazon Basin in South America .
Accommodation is the process by which the vertebrate eye changes optical power to maintain a clear image or focus on an object as its distance varies. In this, distances vary for individuals from the far point —the maximum distance from the eye for which a clear image of an object can be seen, to the near point —the minimum distance for a ...