Do Rats Have Night Vision?
WouterMany scientists wonder if rats have night vision. Rats have two different kinds of cones, one for blue ultraviolet light and one for green light. Rats’ colors are similar to human’s, but their perception of red isn’t nearly as accurate. Rats perceive red tones as a deep tone, while we perceive red as a light tone.
Rats’ eyesight is fairly poor, but not so poor that it can’t be corrected with glasses. The rat eyeballs have a very large depth of focus and the lenses are very small. This means a rat would see nothing even with a 0.3 diopter lens, whereas an eye with two diopters would see everything around it as slightly blurry.
Rats are nocturnal animals that travel in the dark for food. They often scurry away when a light comes on. While they can track urine marks and choose foods by color, their night vision is severely compromised. This is because they lack depth perception and can’t judge size. Rats can detect objects up to three feet away, but their vision isn’t very good at detecting movement or light at a distance.
Rats’ ability to see in the dark may be related to the pigment in their eyes. Rats that are pigmented have a higher level of melanin in their retinas than their albinos. This pigmentation in their eyes allows rats to see better in low light, but it doesn’t mean that they have better vision.
