![]() Natural vision that good is extremely rare, but research by David Williams, director of the Center for Visual Science at the University of Rochester, and his colleagues may soon enable laser eye surgeons to achieve 20/10-or-better vision for a large percentage of patients, placing their visual acuity halfway between that of humans and eagles. Įagles' high-flying lifestyle requires better vision than humans need, and the physical properties of our eyeballs limit us to 20/10 or 20/8 vision at best. But in terms of their ability to solve problems and so on, they match what many mammals can do. "Birds have areas that seem to function like the cortex, but it's arguable. It's more difficult to say how your more sophisticated cognitive processes would fare. Now the question of what it comes at the expense of: most birds appear not to have a well-developed sense of smell or taste," Hodos said. "I would say that birds probably have a greater proportion of their brain volume devoted to visual processing than other groups of animals. After spotting what you're looking for in this manner, you'd redirect your head toward it and use stereoscopic vision - combining the viewpoints of both eyes to gauge distance - to calibrate the speed of your approach.Įnhanced perception and hunting prowess would likely come with a few drawbacks. To locate prey or any other object of interest in the distance, you'd periodically turn your head to the side to sweep your fovea (telephoto lens) across your field of view. With eagle eyes, we would swivel our heads constantly. With our eyes angled 30 degrees away from the midline of our faces like an eagle's, we would see almost all the way behind our heads with a 340-degree visual field (compared to normal humans' 180 degree field) this would confer a clear advantage in hunting and self-defense. On top of the ability to see farther and perceive more colors, we would also have nearly double the field of view. It's perhaps easiest to consider our new powers in the context of how eagles use them: for hunting. Įagle vision wouldn't change how we perform most daily activities - such as reading computer screens or the newspaper, or finding milk in a crowded refrigerator - but how we perceive the world and use our eyes would certainly be different. We can't even guess what they're subjective sensation of ultraviolet light is," Hodos said. "Suppose you wanted to describe the color of a tomato to someone who was born blind. ![]() ![]() But there's no way to know what these extra colors, including ultraviolet, look like. They see colors as more vivid than we do, can discriminate between more shades, and can also see ultraviolet light - an ability that evolved to help them detect the UV-reflecting urine trails of small prey. On top of sharp focus and a central magnifier, eagles, like all birds, also have superior color vision. Some investigators think this deep fovea allows their eyes to act like a telephoto lens, giving them extra magnification in the center of their field of view," Hodos told Life's Little Mysteries. "Our fovea is a little shell or bowl, while in hawk or eagle it's a convex pit. Second, they have a much deeper fovea, a cone-rich structure in the backs of the eyes of both humans and eagles that detects light from the center of our visual field.
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