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Substantial-Turn4979 t1_iud1j32 wrote

Better or poor are tricky descriptors. Animals evolve their senses to be suited to their environments. Humans’ colour vision is amongst the best in the world and have some of the most detailed up close vision in bright light. The trade off was poor low light vision. Other animals prioritize low light vision over perceiving colours. Humans have sharp vision in a tight area directly in front of them but the trade off is poor peripheral vision and no vision behind them. Other animals have an almost 360 degree field of view, but lack a region of extreme sharpness. Each of these different sets of abilities is “better” in a particular set of living conditions.

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MalevolentlyInformed t1_iudge6t wrote

>Humans’ colour vision is amongst the best in the world

Slight nitpick: humans have some of the best color vision among mammals. But most vertebrates see more color gradation than we do. Reptiles, fish, amphibians, and birds are mostly tetrachromats, vs apes/Old World monkeys (trichromats) and other mammals (dichromats). Some invertebrates also have "better" color vision than us.

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Substantial-Turn4979 t1_iudlfdj wrote

I was aware of birds and monkeys, but not reptiles and amphibians. Cool! Thanks for the nit pick.

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Dirty_Hertz t1_iudmkb9 wrote

Doesn't the mantis shrimp have the widest range of color vision including UV of any animal?

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MalevolentlyInformed t1_iudoi93 wrote

I don't know if it's the widest but it's certainly crazy. Anywhere from 8-15 to our 3 cones lol. Plus some can see linear and circular polarized light.

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Resident_Skroob t1_iudt7tb wrote

Whoa. What? To the last sentence.

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Cheetahs_never_win t1_iuegrp8 wrote

Imagine a sine wave to represent a photon. The sine wave is 2d. Now Imagine being able to rotate the sine wave around the neutral axis. To us, the light looks the same. To them, the light looks different.

Normal light is a bunch of these waves at different frequencies and adjusted forwards/backwards in a random fashion.

If you could adjust them such that they're all aligned, which we can do with certain materials that block light paths that come in at the "wrong" angle, but turn the intensity back up, you and I can't tell the difference between the before/after. They can.

And I guess we might not have the vocabulary to describe what they see, but there are some women who are tetrachromats who basically describe colors and patterns only fellow women tetrachromats can see.

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86BillionFireflies t1_iufkea0 wrote

The key piece of information that's often left out is that their color vision is actually terrible.

Picture a movie playing in color. Now picture three black-and-white movies playing side by side: one showing the red channel, one showing the green channel, one showing the blue channel. Same information, but there's a lot of stuff your brain can't actually SEE if the information isn't combined the right way.

The mantis shrimp doesn't combine information across color channels the way we do, for a simple reason: its expensive. It takes a lot of extra neurons to combine different cone inputs in a way that lets you see what we know as color, and neurons cost calories.

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Dorocche t1_iug09yc wrote

How do we know that the shrimp doesn't do that? We can't observe their qualia obviously.

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86BillionFireflies t1_iuhghij wrote

We can do (and have done) experiments to determine how well they can distinguish one color stimulus from another, and they perform worse than humans (and worse than other animals with true color vision).

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ejdj1011 t1_iue67ja wrote

Yeah, but the way their optical perception is wired, they still have worse color perception than humans. Basically, each cone (color sensor) a mantis shrimp has only sees a very narrow band of wavelengths. If a mantis shrimp has 15 cones, it can basically only see 15 specific colors. So while humans only have 3 cones, they overlap heavily and our brains can process the ratio of signals to mix colors.

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