Colorscope_Green_leaves-image
Colorscope: What it really means to see green
01:32 - Source: CNN

Editor’s Note: This feature is part of Colorscope, an award-winning series exploring our perception of color and its use across cultures, one shade at a time. See more here.

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The human eye can see green better than any other color

The color has many associations, from disgust to tranquility

CNN  — 

It’s the color of the Emerald Isle, the hue of sickness and envy, and a shade associated with grotesque monsters. And its most universal interpretation conjures imagery of nature, a vibrant symbol of the environmental movement and healthy living.

Green, the mixture of blue and yellow, can be seen everywhere and in countless shades. In fact, the human eye sees green better than any color in the spectrum.

This, along with many other facts about this earthly color, makes it an essential part of our everyday lives.

But why is that?

Helping you see

We see green with ease because of how light reaches our eyes; the human eye translates waves of light into color.

When we see a green frog, the color that we see is the light reflected off of the surface of the frog’s skin, perceived by our eyes as green.

When we see these colors, the cones in our eyes are able to process the wavelengths and tell the brain what color is being observed.

Humans are trichromats, meaning we perceive three primary colors: blue, green and red. The retina in a human eye can detect light between wavelengths of 400 and 700 nanometers, a range known as the visible spectrum.

Each primary color corresponds to a different wavelength, starting with blue at the lowest (400 nanometers) and red at the highest (700 nanometers).

In the middle of the spectrum resides the color green, at around 555 nanometers. This wavelength is where our perception is at its best. Because of its position in the center of the spectrum, both blue and red light waves are enhanced and better perceived with the help of green waves.

Knowing your environment

Green space sweeps the planet. Before skyscrapers and suburbs popped up, our ancestors resided in forested regions full of greenery.

As they scavenged for food, the ability to differentiate between colored berries against the backdrop of green foliage was critical for survival.

The evolution of eyesight and the increasing ability to detect color with fine detail gave our primate ancestors an evolutionary advantage over other mammals who could not discern such differences as well.

Color changes in leaves, fruits and vegetables can indicate age or ripeness and even offer a warning that something may be poisonous or rotten.

Today, we continue to use this ancestral instinct at a farmers market or grocery store.

Sourcing your food

Bananas, though widely considered to be a yellow fruit, start off as green due to the presence of chlorophyl. Just as grass and leaves have chlorophyll to give them color, so do fruits.

Located in the cells of plants, chlorophyl plays a crucial role in photosynthesis, allowing plants to harvest energy from sunlight and convert it into energy that the plant can use to grow.