Реферат: Land Animal Eyes Essay Research Paper Land

Land Animal Eyes Essay, Research Paper

Land animals have eyes, which adapt to their natural surroundings and help protect themselves from predators, and also help them find food to eat. Every land animal has a different gift which their eyes can do, and the gifts they are given are different, depending on what they are and need to do.The eye is a light-sensitive organ of vision in animals. The eyes of various species vary from simple structures that are capable only of seeing the difference between light and dark to complex structures, such as those of humans and other mammals, that can distinguish minute variations of shape, color, brightness, and distance. The actual process of seeing is performed by the brain and not by the eye, the eye is just the camera and the brain is what makes the picture. The function of the eye is to translate the electromagnetic vibrations of light it receives into patterns of nerve impulses that are transmitted to the brain. The brain then translates this into a picture of what we see.In general the eyes of all animals resemble simple cameras in that the lens of the eye forms an inverted image of objects in front of it on the sensitive retina, which corresponds to the film in a camera.Focusing the eye,is done by a flattening or thickening of the lens in the eye. This process is known as accommodation. In the normal eye, accommodation is not needed for seeing distant objects. The lens, when flattened by the suspensory ligament, brings distant objects to focus on the retina. For nearer objects the lens is increasingly rounded by ciliary muscle contraction, which relaxes the suspensory ligament. All animals have different focusing features, some may need to do this but better than others, as they need it because it may be the only thing that protects them and keeps them alive, as the animal might be weak if they didn t have that. For example a vulture has a very keen eyesight. It can survey large amount of land in one glance plus the center will be magnified by 2 and a half time normal. If they didn t have this feature they would not be about to obtain food for their daily needs.A lot of animals have a lot of features with eyes which humans don t have. For example nocturnal mammals have a glare at the back of the retina which enables them to reflect any kind of light which is visible which can then enable them to see better in the dark. Not all animals have it all good. If they are good and doing something with their eye there is usually something they are bad at. For example The Fox has a very narrow view of sight. This only lets them look ahead and not on the sides of them. They also have a limited colour vision. The positive feature the fox has is that its brain can translate the picture it receives with its eyes, can be translated by the brain to make it extremely detailed, noting everything even small things humans don t even notice.

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