When people say, "that's not a color found in nature!" they're always talking about neon
green or hot pink, but you know what they SHOULD be talking about? Blue!
Blue is a tough color. Yes, the sky appears blue and water APPEAR blue (even though they're
actually not). Though some birds, plants, and butterflies display the color blue, it's
actually a super rare color in nature because it's REALLY difficult for nature to create,
especially since half of the world names blue their favorite color. ComicCon is coming up,
and in honor of my anime and cosplay-loving friends heading down there, sorry we don't
have blue hair… nature, ya know?
The eye evolved 600 million years ago. Before that, the organisms on earth KNEW there was
a sun because they could feel its energy. Eventually, a predator likely evolved a better
way to perceive some that energy and catch prey! That was a huge change in evolution,
suddenly, color was incredibly important for survival. This new predator kicked off a multi-million-year
race to evolve colors to indicate danger, to camouflage, or for sex-differentiation
to hide the breeding females!
Color in the animal kingdom comes from a variety of evolutionary tools. Yellows, oranges, and
reds come from carotenoids in our diet. Cardinals' red comes from insects and berries, and flamingos
absorb carotenoids from algae and tiny animals to become pink (without it, they're just white).
And when we eat red, yellow and orange foods, animals can use those pigments to create color,
but if you fed flamingos blueberries, it wouldn't turn them blue… blue isn't as easy to suck
up… So, instead of using pigments, animals evolved physical structures to reflect light
in just the right way.
By analyzing hundreds of birds, scientists at the Argonne National Laboratory found keratin
inside of the cells of the feathers. Keratin is the same stuff that makes up hooves, hair,
horns, fingernails, et cetera. As the cell grows, the keratin molecules INSIDE the cells
separate from the water in the cell, and once the feather is mature and the cells die, the
water evaporates, leaving this keratin structure -- which refracts light at JUUUST the right
angles to cancel out the yellow and red wavelengths, and only BLUE is reflected! This is called
structural color, as opposed to pigmented color. Our skin can use pigmentation to make
combinations of browns, reds, and yellows, but not blues… or greens, actually.
Snakes and frogs aren't actually green, for example, but they want to hide by sitting
in trees or on lilypads… so they needed to evolve green! Since they can't make blue
pigment and green pigment, they evolved YELLOW pigment to their skin, and a blue structural
color too! Boom green. When smooth greensnakes die, that yellow pigment fades, leaving just
the structures which create blue… So, even though blue isn't a common color in nature,
it can exist, it's just tough. Somehow, thanks to a roll of evolutionary die, fungi, insects,
plants and crustaceans evolved blue pigmentation, but not us vertebrates, and though we don't
know exactly why… at least we can fake it.
Have you ever had blue hair? I had red hair that glowed in blacklight when i was in college.
It was sick...
Click to subscribe, or watch one of these great videos about color!
Easter Egg: "I also had chin-strap facial hair, and that was NOT sick. Well, maybe the bad kind of sick..." -- Trace <3