Guide dogs distinguish traffic lights based on color shades

Guide dogs do not judge traffic lights based on color. Red and green are both gray in their eyes. They distinguish based on gray shades, so that they can Correctly judge traffic lights.

Dogs have a weak ability to distinguish colors

Since the British scientist Dalton discovered color blindness in the 18th century, humans have realized for the first time that not everyone sees the same colors in the world. of! Later, scientists discovered that many mammals are born with color blindness, such as the dogs that are the favorites of shit collectors! What we call color blindness in dogs is to compare it with humans, not to mean that it really cannot distinguish any color.
First of all, we need to explain what cones are, which are cells that sense strong light and color.
Humans have three types of cones that allow us to see all colors in the spectrum. Dogs only have two types of cones, which can only distinguish black, white, gray, blue, purple, etc. well, but cannot distinguish red, green, etc.

Dogs’ vision is about 1/3 that of humans

Dogs are myopic. When converted into degrees, it is about 150 degrees. This means that dogs’ vision is about 1/3 that of normal people. Between 5 and 1/3. Although their eyesight is not that great, dogs have a wider field of vision than humans. Human vision is about 160-180 degrees, while dogs reach 200-290 degrees.
Many people may think that dogs are short-sighted and color-blind and feel very pitiful. However, dogs are only 150 degrees myopic. Dear friends, please feel the thickness of your lenses first!