Why are frogs afraid of bright light?

Because frog's eyes can't see (or can't see clearly) static things, frog's eyes are different from those of ordinary animals and are specially used to see moving objects. Immobile moths and flies are actually unresponsive in the eyes of frogs. However, as long as the moth moves, the frog will find it immediately. According to its flying direction and speed, it will jump up and hunt with its mouth. No wonder some zoologists joked that frogs like to eat flies, but they will starve to death when sitting in a pile of dead flies.

Frog's eyes also have the special ability to recognize different images. It can immediately identify the flies it likes to eat among flying animals of various shapes, and the static background of those flying animals is unresponsive to the frog's eyes. In other words, the frog's eyes are not like a camera. It can not miss all the scenes in front of the camera, but only see the scenes that are useful to it.

Frog eyes can quickly find moving targets, quickly judge the position, moving direction and speed of targets, and immediately choose the best attack posture and attack time.

Frog's eyes, why can't you see the static, but they can see the moving eyes? This has to start with the structure of the eyes:

Look at people's eyes first. The structure of the human eye is very delicate and precise. Its main part is an approximately circular eyeball, just like a camera.

Human eyes have sclera, iris, lens and retina.

The sclera is like the mirror box of a camera. It is opaque on all sides and plays a protective role. It's just that there is a round membrane in front, called cornea, which is as transparent as glass. This is the first pass for light to enter the eye.

The iris is like an aperture, and the round hole in the middle is the pupil, which can be adjusted automatically. When the light is strong, the pupil shrinks, and when the light is weak, the pupil expands, so that the light intensity obtained on the retina is just right.

The lens is the lens, and the light passes through this natural convex lens and spits out an object image in the retina.

The retina is like a negative, which transmits the received image to the brain through the optic nerve and sees the outside world. There are more than1.300 million photoreceptors in the retina, which reach the brain through one million optic nerve fibers. The information received from the receptor is processed by the retina, and then transmitted from the optic nerve to the cerebral cortex, which is further processed to produce vision.

There are two kinds of people's eyes: one is voluntary movement's, which can look up and down, left and right, and see the surrounding objects; The other is a slight tremor that is not controlled by the will. This slight tremor will still occur even when you are staring intently. Sensory cells in the eyes transmit color information to the brain in slight movement.

Look at the frog's eyes again. Frog's eyes, lacking the slight tremor of human eyes and the ciliary muscles that adjust the protruding lens, are actually nearsighted. Things in the distance can't be seen clearly at all, even if there are insects next to them, it will turn a blind eye. Only moving objects can leave images on the screen. Therefore, people put their hands on the roadside and ditches, so that frogs will not be frightened and run away; If people are walking, they will see many frogs jumping around.