September 09, 2018
There has been a misconception that cats can only see in shades of grey, in fact cats see in colour although not the same as us humans. Humans are known as trichromats meaning they have three kinds of cones that allow them to see red, green and blue. Cats are also thought to be trichromats.
Red orange and brown colours appear to fall outside cat’s colour range and are most likely seen as shades of grey and purple, therefore cats appear to see less saturation in colours than humans meaning that colours are not as intense or vibrant. Blue and green appear to be the strongest colours perceived.
So, what are the myths?
Cats and dogs can only see in black and white however scientists have proven this to be a myth, in all animals including humans the perception of colour is determined by the presence of cells in the eye called cone photo receptors. Cats and dogs have two kinds of cones, which are sensitive to blue and green light, this means they have a useful level of colour vision this depends on the presence and types of cones. Cats and dogs are colour blind us humans see in red, blue and green, cats and dogs only have blue and green cones, their perception of colour is muted in away therefore cats and dogs are not sensitive to red light they have difficulty in distinguishing some colours with behavioural tests in dogs suggest that they can distinguish red from blue, but often confuse red and green, they often perceive green as grey. Cats and dogs have evolved so their sight is designed superbly for night time hunting. Their eyes have a high density of rods, which are the cells that are sensitive to dim light. This means they can see normally with as little as 15% of light that humans would need, also their pupils’ function much as the aperture of a camera dilating significantly when they need to take in extra light. Cats especially have exceptionally large pupils for their body size and outstanding night time vision. The myth is cats and dogs can see in pitch darkness, light is still required for the eye to function properly. The skate fish however because it has no cones in the eye can only see black and white.