Hi, my name is Steve.
Today we're talking about bird vision, specifically about how they see colors.
Humans can see lots of colors, but birds can see even more.
Many birds are known for their bright feathers.
Red, green, blue, or a whole rainbow all on one bird.
So you might assume color is important for birds.
And you'd be right.
Birds have amazing color vision.
They can see all the colors you can see, plus more!
Let's take a quick detour to talk about how you perceive color.
Your eye has 3 types of color receptors: red, green, and blue.
So all the colors you can see in the whole world are a combination of red, green, and
blue.
We have names for many of these colors.
Grey, magenta, orange, cyan, yellow, dark orange, and whatever this color is.
Are you still with me?
Okay.
So all the colors on this wheel are some combination on red, green, and blue.
We're going to take one more step back before we move forward.
What if you had only two color receptors instead of three?
If you were missing one of those color receptors, you could not see as many colors.
This is a real-life thing called color blindness.
If you were color blind, here's what it might look like.
Here is a video where everything is red, green, or a combination of red and green (which is,
oddly enough, yellow, but stick with me).
We fly over the Mediterranean Sea looking at the yellow sand, green trees, and the yellow-green
water.
Looks weird until we have a third primary color added in - blue.
Notice how many more colors you get just by adding one color pigment.
Here's another video showing the same thing.
This is what roses would look like if you had zero red color receptors.
And here's the same rose with red.
Our three color receptors give us the whole diversity of colors that we can see.
They combine in interesting ways.
If all your red and green receptors are turned on, they make you see the color yellow.
If all your red and blue receptors are turned on they make you see magenta.
If your blue and green receptors are turned on you see cyan.
And if all three are turned on at the same time you see white.
Many birds have a FOURTH color receptor.
In some birds it's violet.
In others it's ultraviolet.
I'll show ultraviolet here as grey because we don't know what this color looks like.
The name just means it's something "beyond violet".
But birds can see ultraviolet, and it opens up a whole new world of colors they can distinguish,
which we don't have names for.
So here's the color wheel for combining light again.
Let's change the shape a little to add in the fourth color of ultraviolet.
We still have red, green, blue, cyan, magenta, yellow, and white.
We have a name for the new color even though we can't see it.
Ultraviolet.
But we don't have any names for any of these other colors.
It's a big gap where we don't even know what we're missing.
We're color blind to these colors.
But birds see these colors every day.
So next time you look at a bird with all its brilliant colors, take some time to enjoy
what you can see, but also try to imagine all the colors you can't see.
In a future video we'll talk about the crazy complicated vision systems that some birds
have.
Until then, check out my channel page to learn more about birds and maybe subscribe if you
want to know when new videos come out.
Thanks for stopping by.