Find out which famous footballer experiences the condition, what forms of colour blindness exist and that peanut butter is actually not brown for people who experience red-green colour blindness!
The technical term is Colour Vision Deficiency (CVD). It is usually an inherited condition caused by faulty gene-sequencing in the DNA of the X-chromosome.
Dortmund midfielder Thomas Delaney called up Danish radio station P3 anonymously, before revealing himself and his problems. He is apparently red-green colour blind!
Within the retina, photoreceptors called rods & cones are responsible for passing the information received from the wavelengths of light to the brain. While rods are sensitive to the wavelengths of light responsible for night vision, 3 different cone types are responsible for colour vision.
It can also arise as a side effect of some diseases such as diabetes, multiple sclerosis & from some drugs and medications.
There are around 300 million colour blind people in the world – that almost equals the entire population of the United States of America!
Monochromacy is the rarest. It exists when no cones or just one type of cone is available, resulting in vision that can only utilize shades of grey, black, and white.
Dogs possess only two types of cones and like people with severe red or green CVD, they can differentiate between yellow & blue, but can’t distinguish easily between red and green.
Fun fact: There is a whole reddit thread filled with adults startled by the fact that peanut butter is not actually green.
This is because the colour of peanut butter can appear to them to be the same colour as other items which they have learnt are light green.
New-born eyes are monochromatic and they fully develop the ability to see colours only later between 4-6 months.
The English Premier League has earned plaudits for implementing a software framework that detects similar coloured kit clashes for league matches, although the initiative has garnered criticism in recent seasons & especially in 2020/21 as five matches were focal points of debate among the colour blind community.
The mantis shrimp takes the cake with a whopping 16 photoreceptors, just one ahead of the bluebottle butterfly which has 15. This is 4 times the number of photoreceptors that humans possess! They can also move each eye independently!
The 2018 FIFA World Cup held in Russia caused a massive uproar – from the opening matchday between Russia and Saudi Arabia to few quarterfinal clashes.
By contrast, EURO2020 avoided clashes of outfield players’ kits and was applauded by the colour blind community (but there’s still work to do to avoid goalkeeper and match official kit clashes with players’ kits).