Did we lose our ability to see in infrared light ? Or we never had it to begin with ? Does DNA mutations has to do something with it because some have blue eyes instead of brown and they say this is because DNA mutation happened only once in Europe somewhere.


Those animals who hunt in night need vision in infrared light. So, were they first night hunters and then developed vision in infrared (due to mutation in DNA ?) and stayed with them forever according to Darwin’s theory (survival of the fittest) or they realized they had infrared vision and so why not hunt in night only ?

In: Biology

>Those animals who hunt in night need vision in infrared light

No they don’t. Night vision and thermal imagining are 2 completely separate things. Seeing infrared is literally having the ability to detect infrared wavelengths of light. Night vision is just having eyes that are super sensitive even in low light conditions, but it’s still visible light. Some animals can sense infrared but they don’t really “see” it with their eyes, and no mammal is capable of seeing infrared because we make our own body heat, which would render that ability useless. So no, humans never had the ability to see infrared, nor did our evolutionary ancestors, or any other mammal for that matter. Also, the color of our eyes has nothing to do with our vision. That’s literally just pigment, the same pigment that gives us our skin color.

Animal that hunt during the night just have a high sensibility to light and sometime can see just a little bit further into infrared, but it’s not infrared vision.

Some animal can detect infrared, but those are not through the eyes. Usually those are little sensory organ that detect infrared, but they are not as complex as eyes. It just sense the direction from with the infrared come from, a bit like the first proto eye were able to detect the direction of light.

“Those animals who hunt in night need vision in infrared light”

actually no they don’t, true infrared sensitivy requires specialized organs(ie: snakes) and its not in their eyes and even then, they are actually seeing out of these organs, at best they can sense the direction the infrared radiation is coming from.

what these animals actually have is an additional structure inside their eye that helps them trap more light in the eye allowing to see better in low light conditions(this is why animals like house cats’s eyes glow at night btw), they still work within the visible light spectrum.

humans never really had this kind of ability neither did our known ancestors or any regular mammal.