Let’s admit it guys, as far as colors go, mammals are super boring. We have a finite choice for eye, hair, and skin color which all consist of earthly hues. That’s probably why some of us are so captivated by reptiles, fish, and birds who all are vividly colored and varied. It’s also probably why science fiction and fantasy creators always like to slip in the odd looking character or place every once in a while. But what if I told you these alternately colored universes and people aren’t as farfetched as you may have previously thought?
Let’s start with why our earth is so predominantly green. Trees, leaves, and plants all produce a chemical called chlorophyll, you’ve probably heard of it, which makes the plants appear green. By being green the plants can absorb red light more efficiently than if they were any other color. Since our sun emits red light this allows the plants to get the energy they need from the sun to complete photosynthesis. Theoretically, the color of a planet’s sun should influence the color of the plants that grow there, so if a sun is violet the plants would be yellow, you would expect to find blue plants on a planet that had an orange sun, etc. Stars (that’s what our sun is) can actually be any of these colors too! They can be anywhere from infrared to ultraviolet, crazy! For those of you that saw Star Trek: Into Darkness the opening scene with Chris Pine running through the red forest makes more sense now, right? That was actually the made up planet of Nibiru, but it’s totally possible if the planet revolved around a green sun!
Now, why are mammals not colorful? Well, the quick answer is, we’re the top of the food chain, so we don’t have to blend in with flowers, plants, and oceans in order to escape predators, because… we have no predators! Mammals simply have lost the genes to create colorful pigments because they are not needed and the energy could be spent wisely other places. Birds, reptiles, and fish though have many predators and rely on pigmented skin in order to blend in and avoid predation (think about chameleons). So what about Gamora from Guardians of the Galaxy, the Na’vi in Avatar, or other colorful aliens? There are two scenarios where an ecosystem could produce colorful mammals. The first is in an ecosystem where mammals are not the top predators (Jurassic Park, anyone?) and the mammals still heavily rely on pigmentation in order to blend in to their environments. The second scenario is a world where a lack of a pigmentation gene results in differently colored skin. For example, a world where the prey express pigment to all be earth tones to blend into their earth toned environments, and green is the color mammals become when they turn this pigmentation off.
How the color of a planet is determined, or why lack of pigment occurred evolutionarily all makes sense, but seriously, why can’t we at least have colorful eyes? Most people don’t realize this, but the Targaryen family from Game of Thrones are not only supposed to have light blonde, almost white, hair, but they are also described as having purple, or violet, eyes. So what about this, why don’t we have purple eyes? The answer is quite controversial. There have been some supposed cases of violet eyes in individuals with albinism, but it is extremely uncommon. What eye color you have is dependent on 15 different genes (and that’s only what they’ve found so far). These genes effect how much melanin melanocyte cells in the eye produces and when (this is actually why some babies have different eye colors as they age). Blue, green, and hazel eyes actually don’t contain any blue/green colored pigment at all, and only appear those colors due to ‘Rayleigh scattering’ which is the same phenomenon that makes water appear blue. Many people have claimed that Elizabeth Taylor had violet eyes, though many have pointed out that they were blue, but look purple in certain lights. So, purple eyes, theory or reality? Well, in very rare cases albinism can cause an individual to have red eyes that can also appear violet. Seeing as the Targaryen’s are pale of skin and light of hair, oh and also the enormous amount of inbreeding, it could indicate that they are in fact albinos…