Domestic ferrets are just one breed, the colors are the type of ferrets. Within the genus Mustela, ferrets belong to the subgenus Putorius, from which there are only three extant species: M. putorius, the European polecat; M. eversmanni, the Siberian, or steppe polecat; and M. nigripes, the black-footed ferret.
Nearsightedness, also known as myopia, is a common type of refractive error where close objects appear clearly, but distant objects appear blurry. The cornea and lens bend (refract) incoming light rays so they focus in front of the retina.earsightedness, also known as myopia, is a common type of refractive error where close objects appear clearly, but distant objects appear blurry. The cornea and lens bend (refract) incoming light rays so they focus in front of the retina.
Farsightedness, also known as hyperopia, is a common type of refractive error where distant objects may be seen more clearly than objects that are near.However, people experience farsightedness differently. Some people may not notice any problems with their vision, especially when they are young.arsightedness develops in eyes that focus images behind the retina instead of on the retina, which can result in blurred vision. This occurs when the eyeball is too short, which prevents incoming light from focusing directly on the retina. It may also be caused by an abnormal shape of the cornea or lens.