Eagles are recognized as the birds with the best eyesight among birds. The eagle's vision is extremely sharp, under normal circumstances, its vision range can reach 36 kilometers, even in the sky thousands of miles above, the eagle can identify objects on the ground and observe prey on the ground in the air. Therefore, people often call it "clairvoyance" and "eagle eye".
The excellence of the eagle eye is also related to the physiological structure of its eye, unlike the retina of the human eye, which has only one central groove, the eagle eye has two grooves of the central groove and the side central groove, one is used to receive the object image of the front side, and the other receives the object image directly in front, so the vision of the eagle eye is also very broad. In addition, the eagle's pupils are very large, and there is a special structure inside its eyes that can weaken the external scattered light and make the vision clearer.
Of course, if there are birds with the best eyesight, there are also birds with the worst eyesight. If according to the vision standards of birds, kiwi birds are almost a shame among birds, they are different from the generally good standards of birds' vision, generally lying down at night, the main reason is that they can't see the sun during the day, otherwise they are almost blind. Kiwi birds have very poor eyesight, and their eyes are very small. How bad is the kiwi's vision? A few years ago, it was reported that a kiwi bird walked on the ground and crashed into a fence, which can be said to be the so-called "blind eye".
So, in life, do you want to be a very good eagle soaring in the sky, or do you want to be a very poor vision kiwi bird lying on the ground?