Today, it looks like it’s easy to copy colors. That’s not true, though. Blue is a very rare color in nature. It was so late that even in languages, there wasn’t a word for it yet. The world of blue is very interesting.
Think of the names of five animals that are blue, and five plants that are the same color. It’s hard, isn’t it? There is one more thing you should know about the color blue: It’s not as common as you might think. Blue is a common color because the sky is blue, or the color of the sea is also blue. According to a report by Live Science, blue is one of the rarest colors in rocks, plants, and flowers. It is also very rare on animal fur, feathers, scales, and skin.
It is because each of our eyes has between 6 and 7 million light-sensitive cells called cones. With normal color vision, a person has three types of cones in their eyes. Each type of cone is more sensitive to a certain wavelength of light: red and green are the most sensitive, and blue and purple are the least sensitive. Our brain gets information from millions of cones in the form of electrical signals that tell us about all the different types of light that are reflected by what we see. These signals are then translated into different shades of color. Every time we live, we go through this.
Blue in flowers and minerals
When we see a blue flower, like a cornflower, we see it that way because it doesn’t let the red part of the spectrum pass through. Blue is the color that the flower doesn’t like. In the visible spectrum, red has long wavelengths, which means it doesn’t have a lot of energy. It has to be able to make a molecule that can absorb very small amounts of energy. This is so that it can soak up the red portion of the spectrum.
The point is that plants have a hard time making molecules that are big and complicated, so only about 10% of the world’s nearly 300,000 flowering plants have blue petals. Adrian Dyer, an associate professor and vision scientist at the Royal Institute of Technology in Melbourne, Australia, says that blue is very visible to pollinators, like bees, and blue flowers can help plants in ecosystems where there is a lot of competition for pollinators.
Ions (charged particles or molecules) move in and out of minerals’ crystal structures, which affect which parts of the spectrum are absorbed and which are not. Trisulfide ions (three sulfur atoms bonded together in a crystal lattice) are found in the mineral lapis lazuli, which is mostly mined in Afghanistan and is used to make the rare ultramarine blue pigment. That is what makes blue.
Blue in animals
The color schemes of blue animals don’t come from chemical pigments. Instead, they use physics to make them look blue. The blue-winged butterflies of the genus Morpho have nanostructures in the scales of their wings that manipulate layers of light so that some colors cancel each other out and only blue is reflected. This way, only blue is reflected. Cyanocitta cristata blue jay feathers, bluefish scales, and the flickering rings of poisonous blue-ringed octopuses all have the same effect (Hapalochlaena maculosa).
But in mammals, blue tones are less common than in birds, fish, reptiles, and insects, so things are a little weird there, too. Several whales and dolphins have blue skin, as do primates like golden-nosed monkeys (Rhinopithecus roxellana) and baboons (Mandrillus sphinx), which both have blue faces and butts. Most land mammals have blue fur, which is a trait shared by most of them. At least in visible light, it isn’t blue. It turns out that platypus fur glows bright blue and green when it is exposed to ultraviolet rays.
In our eyes, there are three types of light receptors. Birds, on the other hand, have a fourth type of light detector called an “ultraviolet light detector.” Feathers that appear blue to humans’ eyes reflect more ultraviolet light than blue light, even though they look blue to us. Because blue is so rare, the word blue didn’t show up until after the words black, white, red, and yellow did.
Blue in history
People say that only when a color can be dyed and its object’s color is separate does it need to be named. Otherwise, the name of the color doesn’t matter. It took a long time for cultures to learn how to paint things blue or find blue pigments. You can see this in linguistics.
We know that blue dye was used about 6,000 years ago in Peru, and the ancient Egyptians mixed silica, calcium oxide, and copper oxide to make a blue pigment called dirty that lasted for a long time. They used it to decorate statues. An intense blue pigment made from lapis lazuli outside of Europe was as valuable as gold in the Middle Ages. It was used mostly to decorate illuminated manuscripts.
People have thought blue was a high-status color for a long time because it is so rare. Blue has long been linked to the Hindu deity Krishna and the Virgin Mary. Michelangelo, Gauguin, Picasso, and Van Gogh are some of the artists who were inspired by nature’s blues, as well as Krishna.