Imagine: You’re sitting in your bedroom after a long day of work/school. You gaze out your window, staring straight at a wonderful and beautiful scene, with lush green trees, bustling streets, and blinding rays of yellow sunshine.
You look out at this picture perfect sight and wonder could anything be more vivid and colourful than this? This question was rhetorical, of course, but the answer may surprise you, because this world could be more vivid and colourful than we see. This world is full of colours we don’t see.
To understand this topic, you must firstly understand how we see colours. We all have these parts in our eyes called cones, and when cones get activated, we see colour (according to which cone was activated). Cones aren’t activated by colour though, they’re activated by wavelengths/frequencies, as each colour has a certain wavelength/frequency.
Some colours have long wavelengths (red, orange), others have short (blue, violet) wavelengths, and some have medium wavelengths, (yellow, green). To see colour, our cones first sense wavelength, after that the according to the wavelength, a cone gets excited. Finally the brain sees the cone got activated, so it shows us the colour.
Our eyes only can only comprehend wavelengths of 400-700 nm according to N.A.S.A, a company that has revolutionised the world with sending man to the moon and more. Since there are still wavelengths ranging from more than 700 nm, to less than 400 nm, we know for sure that there are more colour out there.
These colours are ultraviolet and infrared. Colours with wavelengths less than violet are called ultraviolet, meaning a violet to violet we can’t imagine it. Colours with wavelengths longer than red are called infrared, meaning a red so red we can’t imagine it. Here is an image from that shows you the colour/light spectrum.
If we can’t see infrared or ultraviolet, how do we know it’s real? Well, we can’t see them, but we can feel them. When you go near an electric stove or a campfire, you feel a heat (without touching the fire). This heat is in fact infrared light.
Ultraviolet is also heat related, as ultraviolet light is the light that gives you sunburns. Our body is extremely sensitive to ultraviolet light, that is why it gives us sunburns. This is all proved by an experiment conducted by Samuel Pierpoint Langley, he got a prism and let light flow through it, the spot the prism was directed at, became hot, due to ultraviolet light.
You might be thinking why should we care for colours that we can’t see. It’s not like anyone can see them. But that is where you’re wrong, certain beings can see them. Animals can have different amounts of cones, so some animals do see more. For example dogs only have 2 cones (green+blue), so they see less than humans, they may not be able to see the fiery reds, and bubbly oranges we see.
Butterflies on the other hand, have 5 cones, they can see so many more colours. They may see shades and blends of unknown colours, and new shades of known ones two. Imagine looking through a butterfly's eyes, fluttering to each flower, seeing so many colours, and shades, unimaginable to humans.
Butterflies have sharp vision, they can see things that happen really fast. They can also see ultraviolet light, so they can see light with extremely low wavelengths, but they may not be able infrared, or other long wavelengths (even red?). The thing is we’ll never know for sure, because we cannot see through a butterfly’s eyes, so we’ll probably never know what they see.
You may be thinking that nobody can beat butterflies, but you’re wrong there’s an animal that has loads more cones than a butterfly. This animal has about 5 times the amount of the the butterfly, it has 16 cones. This animal is the mantis shrimp.
Mantis shrimps are miraculous creatures, as their world will be so different than ours. Imagine looking through a mantis shrimp’s eyes, seeing the world in all the vibrant colours that appear everywhere. Our eyes may seem boring or weird according to a mantis shrimps. Just think on how different the same world can be depending on who’s looking.
Here's a simple, and interesting video with these facts.
Finally, I will tell you about humans that have more than 3 cones. Yes they exist, they’re called tetrachromats. Tetrachromats are only female. These people probably can’t see different colours all together, but they have very strong vision. If you had 2 paints of the exact same shade of green, but one was a natural green, and the other was a yellow and blue mix green, tetrachromats will be able to see the difference immediately, .
Tetrachromats see different colours where we don’t see them. According to a tetrachromat names Concetta Antico, who was an artist/teacher “I’d say, ‘Look at the light on the water – can you see the pink shimmering across that rock? Can you see the red on the edge of that leaf there?’” This is how the world looked to her, though not to her students,
Now I know you’re wondering why we should care about this, we should care, because we use all these invisible colours/lights to make machinery and other things, and we will continue to use them to make new technological advances. There is a motion sensor that works because of infrared light, it is being used to help patients with cerebral palsy, a condition that makes it harder to move. It tracks patient's movement, and helps people see where the problem is.
Video with more on infrared used for motion sensor. Motion sensor part starts at 5:20
In conclusion I’d like you to think about how everyone sees the world differently, and how you can take this look on life. It’s so important to see and understand how other beings live, because they’re always full of surprises and secrets. So next time you look out your window I hope you wonder what are other beings seeing right now?
Credits:
Created with images by chileantait - "View at the rainbow above the road" • Robson# - "Colour wheel" • m01229 - "Colorful flowers" • 23rd Studios - "untitled image" • mrRobot - "yes Virginia, there is a munchkin" • arewethereyet? - "Butterfly" • Ed Bierman - "Mantis shrimp or stomatopods"