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Comment by falsedan | Hacker News Reader

All of your examples are related to food acquisition. Consider /imagine the non-sighted analogues of them, and how 'successful' they are/would be e.g. a worm the size of a mole[0] & how trivial it would be for predators to prey on it.

[0]: not these ones tho https://en.wikipedia.org/wiki/Giant_Gippsland_earthworm

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yes i guess the evolution of our vision was driven in part by hunting (being able to resolve animals at a distance) and gathering (being able to discern colours of berries)

also the medium in which we primarily exist (i.e air). If we existed in water, or in soil, then the collection and classification of light would not be as important.

I think the vast amount of seeing marine creatures is a massive counterexample. Evolutionary biologists think that the ability to detect any photons grants an advantage: in environments where there is light, eyes evolve, even when the light is dim. It's only in completely lightless environments that eyes no longer provide an advantage (i.e. abyssal plain or caves).

Agreed, the sea creatures have evolved to capture even more light. I'm only guessing, but I would think the pressure and temperature sensors on fish would be more important than sight?

You mean, sensors to detect at a distance? For temperature, most deep-sea creatures have large amounts of insulation to survive the cold & thus would be difficult to detect (especially since water is also an insulator). For pressure, those exist and are called tendrils/antennae.

My point is: these creatures evolved more specialised senses to improve their food-gathering, but they also all have eyes. Perhaps eyes convey a general advantage, regardless of how you find food?

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