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Having worked extensively at several companies in the 1990s trying to bring optical measurement of objects into production environments, I assure you that a lot of that bumpiness turns out to be artifacts of the measurement process.

As just one example, there's really no laser-based measuring device in the world, even today, that can rapidly measure a surface near (<1mm) the edge of an object. Something that is trivial to do with ruby-ball touch sensors...

No. We live in a world full of wavelengths. Our brains are giving us a way to see them.

The laser scan is further from the truth of reality than vision as it has less information about reality captured & displayed.

If you want to go all misanthropic, it is much closer to reality to say that we see only a small slice of what is in fact a world colorful and detailed beyond all human ability to comprehend any but a small slice of it. The "creepy gray horror movie render" is the farthest thing from the truth, not the nearest.

There is reality, then there are views/models of reality constructed via various different ways of sensing reality, whether that's a laser-scan depth map, normal human 3-color vision, occasional human 4-color vision, animal UV-sensitive vision, mass detectors, magnetic/electrical field detectors, etc, etc.

Why should we regard one extremely arbitrary way of sensing reality as more important or real than any of the others? Why is reflected light important, not absorbed light? Why visible spectrum vs other frequencies? Why human red/green/blue color cone detection (which is no such thing - they are overlapping curves of frequency spectrum sensitivity)? Why focus on light reflection, not sound? Why focus on surface attributes of objects such as "color" rather then regard other attributes such a mass distribution, or anything else as primary?

In a way, you are on the right track, but the conclusion is different. What we live is far from gray, rather it's unfathomably more "colorful" and chaotic. We do see just a bit of it and apply a lot of filters to it, that is true. But it's mostly to dampen the environment, not to enrich it. (Not that we don't enrich it as well.)

What I think the most important part is of your comment is how profound is to look at reality with a different lens. Be that a false color image like a laser scan, heatmap, space images, xray, microscope... it can be a really intense experience, just as you describe. Learning about the different filters (biases) that the brain puts on the stimuli is quite mind-boggling as well.

The bumpy grey mass is where the matter is.

The colors you see is what kind of light the matter reflects.

Both are real!

> That is actually reality

No, it is just yet another incomplete view of reality. For example, where are the infrared wavelengths in that scan? How can you say "that is reality" if it doesn't include that information? You might argue there are no true views of reality, that all views of reality are only some incomplete interpretation of it.

We see only some minimal set of what is necessary for us to see in order to survive with just enough certainty that we haven't gone extinct.

It goes beyond, your brain will also add an emotional bias on certain patterns depending on how it fit our needs of the time.

Anecdotally it's quite "magical" that nature ended up as 80% beautiful landscape (and sometimes the occasional horrendous sight) as if beauty is an emergent property of the biosphere..

That’s not actually reality. It’s a facet of what form of energy is there.

To generate a natural-color image of a biological sample using lasers in the human eye's visible light range, you'd need a great many lasers covering the entire frequency range. This generates hundreds of datasets at each particular wavelength (ignoring issues like laser-induced fluorescence, which can be managed with spectral filtering).

The trick comes in taking all that data from the hundreds of images generated by different-wavelength lasers and assembling them layer-by-layer into an image the human brain interprets as color, aka colorimetric rendering, onto the three-color-cone system the eye's retina employs plus a bunch of neural processing (there's a complex equation for this mapping of 'hyperspectral cube' data onto an RGB display for human visualization).

There's a really strange example - the mantis shrimp - that used to be thought to have rich color vision in a narrow band, but now people think it might be a lot more direct, a kind of color vision without much neural processing involved, with each photoreceptor scanning slighty different wavelengths and directly signalling to the mantis brain, such as it is:

Thoen et al. (2014) – "A different form of color vision in mantis shrimp" (Science)

https://www.science.org/doi/10.1126/science.1245824

What we see doesn't exist and we what exist we cannot see.

Flowers will happen. Most “white” flowers actually have landing strips painted on them in ultraviolet.

>Video on the internet was not a popular thing until we had broadband internet.

I think it's an example of a post hoc fallacy. The popularity of video was in large part responsible for the investment into broadband in the first place.

We LOST infrared and UV vision by being little shrews scurrying in darkness from glorious five-color-receptor-vision dinosaurs. Even the third color we apes have we had to re-invent.

A lot of insects can see in UV.

Edit: interesting article here- https://en.m.wikipedia.org/wiki/Ultraviolet_communication_in...

> Feathered dinosaurs are known to be colorful

Perhaps because it's not truly known.

> The discovery "suggests a more colourful Jurassic World than we previously imagined,"

-- from your link

The article likely distinguishes between simply having colors versus evolving colors specifically for sexual selection - fossil evidence can show dinosaur coloration but determining behavioral purpose is much harder than observing living fish species.

Bacteria can be colorful. It can also fluoresce.

My blood is red because it has iron in it not because there's an evolutionary link to my eyesight.

Under a thick canopy it basically is like that.

Well then leaves would get too hot and plants can’t absorb unlimited sun

They need to absorb red and blue light

I think you're right. A specific example would be chlorophyll. Chlorophyll is green, not because green was selected for. Instead, it's just a side effect of the biochemistry needed to absorb energy from sunlight.

That's assuming the only purpose of color vision is to see the colors of other living organisms.

There's color in nature beyond life, such as in minerals and other chemicals. There's also color in life that isn't necessarily meant to convey something —such as the green of plants or the red in blood— that could be useful for finding food, for example. Interestingly, hemoglobin seems to have come to be > 400 mya too [1].

Moreover, color can help with contrast in vision. Two materials could reflect the same amount of light, but in different wavelengths.

[1]: https://www.ox.ac.uk/news/science-blog/ancient-blood-lines-t...

Sure, color corresponds to a physical property, so obviously there were things of different colors (sunlight, water, rainbows, rocks) before life developed. Everything has a color.

Color vision (or just ability to differentiate 2 or more frequencies of light) could have evolved a soon as there were forms of life for who this was advantageous - potentially as simple as an ocean organism orientating itself towards sunlight.

It seems the co-evolution of the property of color and color detection ability in plant and animal species, must logically have followed a basic ability to differentiate non-evolved natural colors.

You are assuming that a random mutation will cause all colors to be equally likely. But, AIUI, there is a reason that all your standard chemical powders in a normal chemistrly lab are white; colors are a rare side effect of certain molecular properties. Most chemicals, variated randomly, are extremely boring colors, mostly white.

Almost. Reflectance is how we quantify an object's ability to absorb and reflect light. This is the physical reality, unconstrained by biology. Color is a sensation; how we perceive the reflectance based on our trichromatic vision.

After reading:

It turns out I didn't grasp what the authors meant by "colorful signals". They're talking specifically about vivid colors that serve an evolutionary purpose, and in that case it seems rather clear that vision would have to come first. That is in fact also what turns out to be the findings.

While the article is a fun and light read about some scientists doing some literature review to try and approximate when color as a signal evolved, I'm afraid the error bars are so large it's hard to find any certainty.

The article does end with some speculation that vivid color can't actually evolve without eyes that produce a natural selection bias, since vivid color takes effort to construct. That claim of course has the same efficacy problems as what the article is mainly dealing with, but I do find it somewhat convincing, and have lowered my certainty that vivid colors actually evolved first.