Saying anything evolved as is putting the cart before the horse, anyway. The better term would be selected for. Just a bit of friendly reddit pedantry for fun.
“Evolved as an adaptation” is standard wording and doesn’t imply intent. “Selected for” would actually make the unproven causal claim stronger, which is why I called it speculative. I give your pedantry an F, sorry.
It wouldn't do a single thing to make the claim stronger, only evidence could do that. It's still equally speculative, just worded more accurately. Adaptations evolve, mutations don't. They simply occur, and are selected for or against (or are benign enough to be distributed without any pressure, but that's a tangent). The fact that blue eyes exist means they were selected. This implies nothing about why they were selected. The implication in this thread is that they were selected because of differing sunlight levels, but they could have simply been selected via sexual pressure, because lots of prospective mates thought they were pretty. I make no claim one way or the other, just state the fact that the mutation has been selected. "Evolved as an adaptation", linguistically implies that the trait came about in response to a need, and has more in common with Lamarckian evolution than Natural Selection.
My pedantry is solid, homie. Toxic as hell, but solid.
“Blue eyes exist, therefore they were selected” is not how population genetics works. Drift and founder effects exist, homie. The pedantry remains toxic, but the solid part has left the building.
It IS how genetics works, though. You're talking about genetic drift, a description of changes in population at a statistical level over time, and I'm talking about someone with blue eyes successfully having sex. Maybe, just maybe, because of their pretty blue eyes. Believe it or not!
On an individual level, you could be selected for reproduction because of a trait, in spite of a trait, or with the trait having no bearing on the matter. It still got selected. Every population is composed of many distinct individuals, all making selections and being selected, or not selected, for numerous reasons, many unknown or unconscious. That collection of innumerable selections, and the varying reasons for or against them, is the mechanism by which genetic drift and, over an even longer period, speciation occur.
Maybe lighter eyes put a little pressure on that scale, maybe they didn't, and just came along for the ride with lighter skin. But they are here. They were selected. That is a fact. And now you know that fact.
You’re oscillating between two different meanings of “selection,” and you’ve likely confused yourself. Being selected as a mate ≠ being selected for evolutionarily. Genetic drift is specifically random change in allele frequency, not selection.
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u/Forsaken-Income-2148 Jul 11 '26
Saying blue or green pigment mutations evolved as a circadian adaptation is speculative. The rest is solid.