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How do animals adapt their eyesight in the midnight zone?
Question Date: 2017-08-26
Answer 1:

There are two kinds of adaptation, one is by evolution, which takes generations. So animals that are active at night (nocturnal animals) have evolved eyes that see well at night. Another type of adaptation is a temporary change in one individual, usually in a short time. These changes are not passed on to their offspring. For example, getting used to hot or cold temperatures is this kind of adaptation.

One evolutionary adaptation for seeing at night is having big eyes Big eyes trap more light, just like a bigger window takes in more light. Another adaptation is having more light receptors that work in dim light (rods). The light receptors that let us see color (cones) need bright light to work. That’s why everything starts looking gray in dim light.

Another adaptation is having a sort of mirror at the back of the eye that bounces light by the light receptors again. If you look at most flashlights they have a mirror behind the bulb for the same reason. You can tell whether an animal has this “mirror” because their eyes seem to glow when light shines on them.

An important temporary adaptation is the pupil of the eye getting bigger. The pupil is the hole that light goes through to get to the light receptors. It looks black. The iris is the colored ring around the pupil. Your iris might be black, brown, blue, green, or other colors like that. The iris controls how big the pupil is. If it opens up, more light gets in. So pupils get bigger in the dark when the iris opens more.

If we only saw in black and white, we could see a lot better at night. Why do you think being able to see color might be an advantage?

Thanks for asking,

Answer 2:

Are you referring to the midnight zone of the ocean? They can't - they still need light to see. A lot of animals make light, however, so animals can see that. Additionally, animals tend to evolve very large eyes that deep in the ocean, so that they can see the sparse light from bioluminescent animals and from themselves.


Answer 3:

Some animals in the midnight zone emit light, which is called 'bioluminescence'. Then they can see each other. Some animals in the midnight zone don't have eyes. Here's a short wikipedia article:

Bathayal zone


Answer 4:

Please read a wonderful answer on the link below:
animal-sight


Answer 5:

I will assume you mean “at night” when you refer to “midnight zone”. Animals that hunt or gather food at night have adaptations to the structure of the eye that ensures it collects as much light as possible. For example, an owl has HUGE eyes that take up the majority of the skull. The bone that makes up the eye socket looks like a tube and functions to further direct any small amount of light (for example faint moonlight) into the back of the eye where it hits abundant and very sensitive light-sensing cells. These adaptations allow the owl to essentially see in the dark.



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