After black and white, that is, the contrast of dark and light, red is the first color that babies can detect. Also, red is the last color that can be detected by people who are losing their sight and the first that they see in case their vision returns after blindness and the first that we can detect in case of loss of consciousness after regaining consciousness. After white and black, red is the color that appears most often in nature and that evokes the strongest emotional response.

Strictly scientifically speaking, red belongs to that part of the visible part of the electromagnetic spectrum that has the lowest frequency and the highest wavelength from 620 to 740 nm. Wavelengths greater than 740 nm cannot be seen by the human eye, but we can feel them as heat.

This is one of the most common colors in nature. We are surrounded by various red pigments of inorganic or organic origin. The red shades of the earth – ocher and sienna come from iron oxides, and these were the first pigments that people used.

It can be found in many shades – vermilion, carmine, burgundy, coral red, magenta, scarlet red, etc. It used to be obtained in different ways: from some types of insects, snails, plants and from minerals that contained iron, such as hematite.

The most famous and most available red pigment was obtained from the dyer’s broch, Rubia tinctorum , which was known to the ancient Egyptians.

The much more expensive red pigments are those obtained from several types of insects: Laccifer lacca (synonym Kerria lacca), a type of aphid that lives in India, and Dactylopius coccus from Central America. Carmine red and vermilion are obtained from these insects. Also, a Brazilian tree, Caesalpinia is also the source of a type of red-orange pigment called brazilin. By the way, other plant red pigments belong to the group of anthocyanins – pigments that we see when the leaves lose their chlorophyll in autumn, which “masked” the anthocyanins.

Carmine red color is used in cosmetics and the food industry. Yes, from plant lice.

The uniforms of the English army were red, which is why the soldiers were called “red coats”, except that the uniforms of ordinary soldiers were dyed with dye broch, and the officers’ uniforms with cochineal, obtained from the louse Dactylopius coccus .

The brick shade is the color of the mineral cinnabarite, which is mercury (II) sulfide by composition and is one of the most important ores of mercury. However, this ore is extremely toxic and its mining is dangerous. Ancient Romans sent the worst offenders to cinabarite mines, which was a guarantee of a slow death.

However, physics cannot explain how the color red affects mood and motivation or why our brains are so attracted to red.

Anthropologists have tried to provide some explanations. Namely, the primates of the Old World, the great apes, have trichromatic vision, that is, they have three types of opsins – light-sensitive proteins, which enables them to register all the colors of the visible part of the electromagnetic spectrum. Lower primates cannot do this because they have dichromatic vision, and their color sensitivity is narrowed to the blue and green part of the spectrum. One explanation is that red color discrimination allows these primates to distinguish ripe fruit from unripe and from leaves in tropical forests, and to distinguish dry and tasteless leaves from young and fresh ones.

The theory is simple and sounds good, but it is still unconvincing. Other anthropologists believe that the sensitivity and psychological response to red arose in order to be able to recognize females ready for mating with redness of the genitals.

Female torso, by me



One study from 2004 showed that football teams wearing red jerseys statistically have a higher chance of winning, while another study shows that men rate women dressed in red as more attractive. Our subconscious really perceives the red stimulus as a sign of dominance or encourages competitiveness and self-confidence in those who wear red clothes. These theories also sound attractive, but have not yet been exactly proven.

We associate this colour with excitement, tension, passion, love, war, blood and danger.

Redroom Twin Peaks, Lynch manner

We also associate all other colors with some emotion. However, not because a certain color really evokes a specific emotion, but because we, over many years and generations, have attached a certain context to a certain color. The brain did not evolve to see the world as it is, but to see what was useful to the organism in the past. We are defined by our environment and the way we interact with it.

And our body and our genetic information are a kind of translator for us in this confused world. Our color perception is a consequence of the way our brain interprets color, not the actual picture of the world. For natural selection, it is not important whether that image is correct or not, but whether it enables one to find food, shelter, escape from enemies and find a partner. If not, you die and your genes are not passed on to future generations.



Jelena Kalinić, MA in comparative literature and graduate biologist, science journalist and science communicator, has a WHO infodemic manager certificate and Health metrics Study design & Evidence based medicine training. Winner of the 2020 EurekaAlert (AAAS) Fellowship for Science Journalists. Short-runner, second place in the selection for European Science journalist of the year for 2022.