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2007-06-26 06:25:54 · 6 answers · asked by Anonymous in Science & Mathematics Biology

What part of their eyes affect the eyesight etc.

2007-06-26 06:33:09 · update #1

6 answers

Not many animals have better eyesight than humans...but ones that definitely do are raptors (birds of prey, like hawks). They fly high above the ground, and need good eyesight to see prey that is hundreds if not thousands of feet away. The lens in the eyes of these birds is the difference maker; they can 'telescope' in, changing the shape of the lens in the eye much more dramatically than a human. They also have extra sets of eye muscles, and more photoreceptors in their eyes; to think of a digital camera, the result is having a longer zoom and more pixels than a human eye. In terms of night vision, the size of the iris will affect this. Animals which can open their eyes further can let more light in; this means they can use more of dim light sources. Cats are good examples. Finally, eye orientation affects vision too; animals which hunt (like humans, hawks, and cats) often have their eyes facing forward. Their fields of vision overlap, allowing them to judge distances effectively. Grazing animals (Many fish, cows, etc.) usually have eyes on the sides of their heads. This means they can see more, although they have a hard time determining distances, since the two eyes cannot compare images with each other.

2007-06-26 06:47:00 · answer #1 · answered by harvityharvharvharv 3 · 0 0

Improve Your Eyesight Naturally

2016-05-14 11:35:12 · answer #2 · answered by Anonymous · 0 0

1

2016-06-19 05:19:07 · answer #3 · answered by ? 3 · 0 0

For the same reason some animals can run faster than humans, can smell better than humans, are stronger than humans.

All we have is a big brain to better plot against the rest of the animals that can do so many other things so much better than we can.

As per previous answer, this is natural selection in action.

2007-06-26 06:36:16 · answer #4 · answered by Joan H 6 · 1 2

Animals are all different - the ones with better eyesight are most likely nocturnal - thus they need to see better because it is dark

2007-06-26 06:34:20 · answer #5 · answered by the_hilton 4 · 2 0

They need it, either for finding food or avoiding being food. Natural selection at work.

2007-06-26 06:29:26 · answer #6 · answered by Anonymous · 3 0

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