Why can humans see color?
By Jordyn Pierre-Raphael 

As humans, we have the tendency to take things for granted because we assume that they are long lasting or permanent. Things like our health, our life, or our vision are seen as steady and dependable, and because of that, they begin to blend into the backdrop of our daily lives, which causes us to value them less. Our vision, for example, is often perceived as our most astounding ability, yet it is not always cherished as the world around us painted with a myriad of colors is taken for granted. This just goes to show how deeply colors can become lodged in our mind; people see so many beautiful colors, from the bright reds and beaming blues of wildflowers, to the pinks and purples of a sunset. These are just a few of the rainbow of colors we see today, but if you were to ask someone why and how we are able to see color, it is fair to say that they may not many would know. Seeing colors is a complex concept that many do not know or do not care to understand since the idea that every object has a distinct color has become ingrained into our minds. When growing up, children, are taught our basic colors and learn that the sun is yellow, the sky is blue, or that roses are red. What they are not taught is that objects do not really have a “color,” instead it is the relationship between the cones in the human eye and the light reflected off of the objects that allows us to see “colors.” Light is a form of electromagnetic radiation, which is a type of energy that travels in waves and is measured by its wavelength (in nanometers), and together, all of the waves of electromagnetic radiation make up the electromagnetic spectrum. This, in itself, is a large spectrum of wavelengths, however, only a part of the electromagnetic spectrum can be seen by the human eye, and this is known as the visible light spectrum. Each wavelength on this visible light spectrum corresponds to a specific color that we see, and this means that shorter wavelengths correspond to blue and violet and longer wavelengths correspond to red. When you look at an object, the wavelengths of reflected light will ultimately determine what color you see because the human eye will see these reflected light waves and then send a message to the brain telling it that the object is a certain color. If light hits a banana, for example, all other waves are absorbed by the banana, while the waves that correspond to the color yellow are reflected off of the banana peel and hit the light-sensitive retina, in which the stimulation of the cones of the retina occur. The stimulated cones, which are the tiny cells that respond to light, causes the visual cortex of the brain to process the information and discern that the color of the banana is yellow. Contrastingly to other colors, if you were to see white, like when you stare at the sun, this is actually not one color, but rather it is actually a combination of all of these colors on the visible light spectrum. It is quite evident that our ability to see life in colors affects our lives as so many objects are associated with a color as a means to convey some sort of message; for example, on a traffic light, green means go, yellow means slow down, and red means stop. Not many stop to think of the privilege they have as they are able to see life in color because they take it for granted. It is easy to do this, but there are many who do not have the ability of seeing all the colors due to colorblindness or other eye ailments. This is why more people should think and know more about why and how we see color, so that we do not take this ability for granted.

Citations: Human Vision and Color Perception. (n.d.). Retrieved April 02, 2018, from https://www.olympus-lifescience.com/en/microscope-resource/primer/lightandcolor/humanvisionintro/.
Light and photosynthetic pigments. (n.d.). Retrieved April 02, 2018, from https://www.khanacademy.org/science/biology/photosynthesis-in-plants/the-light-dependent-reactions-of-photosynthesis/a/light-and-photosynthetic-pigments. Pappas, S. (2010, April 29).
​How Do We See Color? Retrieved March 26, 2017, from http://www.livescience.com/32559-why-do-we-see-in-color.html.