The point is that "color" does not physically exist[1], it is a construct of human perception and language. Thus you cannot scientifically study color at all--if you try, what you are actually studying is human perception and language.
This is not an unscientific concept, because human perception and language are naturally occurring, albeit incredibly complex, phenomena.
Animals do not see colors, they react to physical phenomena including photons. Humans use the concept of color to describe what animals do.
Certain animals who learn human language can communicate with us about color. That doesn't mean they can't think, it just means that color is a human construct so they need human language to reason about it.
[1] What physically exists are photons across a range of frequencies, but that's not the same thing as color.
> Animals do not see colors, they react to physical phenomena including photons.
Come on. This is a roundabout way to try to define animals in terms of what they don't have -- not color perception, which many animals have, but words to describe the colors.
Of course animals see colors, in the most basic biological sense. Many see colors more efficiently than we do, indeed see more colors, colors we can neither imagine nor name.
> ... it just means that color is a human construct so they need human language to reason about it.
Believe me when I tell you, animals don't need us to tell them how to reason about color. Why do you think the Peppered Moth changed color over a period of 150 years? It was the only way the species could survive their changing environment and the acute visual sense of their predators.
> What physically exists are photons across a range of frequencies, but that's not the same thing as color.
No, what we call "color" or "color perception" is the biological sensing of electromagnetic energy, which many animals have. So, since we and animals have color perception, and since some animals do it better than we do, the argument has no substance.
While we're on the topic, here are my favorite colors:
* Unforeseeable fuchsia, the color you never see coming.
* Statutory grape, the color of a dress worn by a 13-year-old girl.
You're basically doing what I said people do, which is to use color to describe how animals act. That does not mean that color, as a concept, has any meaning in the mind of an animal.
The electromagnetic spectrum is continuous; our concept of color is a completely arbitrary way of dividing it[1] up into sections. That was the point of the Radiolab episode (and a lot of academic research before it): different human cultures divide up the electromagnetic spectrum in different ways, each of which is as valid as another.
Animals might not have this concept at all; for example it would be just as physically valid to think of the electromagnetic spectrum the way we think about sound--as a continous spectrum from "quiet" to "loud". We know that divisions are arbitrary when it comes to sound--that's why the "this amp goes to 11" joke in Spinal Tap is funny.
The frequency of the perceived light coresponds roughly to color. The frequency of the perceived sound corresponds roughly to pitch. So I think that "quiet" to "loud" is analogous to "pale" to "bright", when it comes to visible light.
>>different human cultures divide up the electromagnetic spectrum in different ways ...
Yep, different human cultures divide up the sound spectrum in different ways too ... So what ?
Some people have absolute pitch perception, allowing them to reproduce a musical tone, that they had heard exactly, even without knowing its proper name, just like some people can distinguish between color hues, that other people lump together as generic "pink", "green", "blue" or "yellow".
Having a vocabulary of specific names may ease learning/training, but it seems to me, that no matter how many different words for colors you teach a child with daltonism, the child will still fail a color blindness test.
This is not an unscientific concept, because human perception and language are naturally occurring, albeit incredibly complex, phenomena.
Animals do not see colors, they react to physical phenomena including photons. Humans use the concept of color to describe what animals do.
Certain animals who learn human language can communicate with us about color. That doesn't mean they can't think, it just means that color is a human construct so they need human language to reason about it.
[1] What physically exists are photons across a range of frequencies, but that's not the same thing as color.