Colors make everything look beautiful; you cannot even imagine your surrounding being colorless. But do these colors really exist? Or is it just imagination of our beautiful brain? Are black and white not considered as colors? And do different organisms see colors differently? These are some of the questions on which we will have healthy discussions in this very article.
To understand colors we first need to understand little bit about light, because light is something that stimulates sight and makes colorful things visible. Firstly let’s understand how light; which is a form of energy, produces sensation of vision?
Actually when a beam of light falls on an object from the source of light (sun, bulb, etc) then this light gets reflected in all directions after striking that object. The reflected light then reaches our eyes and the image formed on retina (it is a thin layer of light sensitive tissues where image is formed) is what brain process and tells you. This is how we are able to see objects around.
But, how this white light makes us to see such beautiful colors? Let’s first understand what this white light is made of? In visible spectrum, White light is composed of 7 colors (the colors we see in a rainbow VIBGYOR). All these colors have different wavelengths where, Red has the highest around 700nm and Violet has lowest of around 400nm. Let’s travel in past, a while ago when we were trying to understand how light is reflected by objects is received by our eyes and enables us to see, when this white light is incident on any object it has all 7 colours in it, but when this light is reflected back from the object, it does not contain all the 7 components but some colors are absorbed and reflected back by the object due to the property of that particular object also intermixing of some colors takes place. So, the light reflected back from object contains a different set of colors; human eye (light receptors) and brain together translate light into color. Light receptors within the eye transmit messages to the brain, which produces the familiar sensations of color
Thus, we can say color is not inherent in objects. Rather, the surface of an object reflects some colors and absorbs all the others.
Everything you see around would have not very colorful if light was absent from this world. So, light is something that ishwar (supreme energy) has used to color this universe. What will be the color of this world around you without light? Will it be black and white? Well, Area where no light is reflected either because whole light is absorbed by the object or because of absence of light, appears dark (Black) and the places where whole light is reflected back with no absorption by object appears white. Now you decide yourself, Can you even consider black and white as colors?
The light receptors in retinal wall of eye are the main reasons for making our vision colorful. There are 2 types of photoreceptors in the retina: rods and cones, Rods are responsible for vision at low light levels (scotopic vision) and Cones are active at higher light levels (photopic vision), are capable of color vision and are responsible for high spatial acuity. There are 3 types of cones in human eye.
Now let’s try to see through the eyes of some other creatures of this planet.
Human eyes contain three types of cones (color detecting cells) whereas dogs have just two. Their cone cells are specialized for picking up yellow and blue-to-ultraviolet light. Due to fewer cone types, dogs can’t distinguish between as many colors as we humans can.
Snakes generally have poor vision, but they can see thermal radiations even at night ten times better than any modern infrared technology. During the day, however, they only react to movements.
Bees comprehend the world three times faster than humans do. They also see ultraviolet rays that we’re unable to.
Butterflies are amazing insects. Their vision isn’t very sharp, but they can see many more colors and shades than human beings can, including ultraviolet light.
There are many more animals with amazingly different vision. As we see here not every creature on this planet is limited to visions under visible region of Electromagnetic waves. Every creature on this planet have got a sort of super power vision that they can see other regions of light spectrum too (UV, infrared, visible, etc).
Everything of this and all other existing universe is very beautiful; you just need beautiful vision to color and experience it and I don’t think these photosensitive visions are enough to experience this beauty.