Those are things we do while asleep, but do not explain why we sleep. Why did evolution settle on that path, with all the dangers of being unconscious for 4-20 hours a day depending on species? That variation is already pretty weird just by itself.
Worse, evolution clearly can get around this, dolphins have a trick that lets them (air-breathing mammals living in water) be alert 24/7, so why didn't every other creature get that? What's the thing that dolphins fail to get, where the cost of its absence is only worthwhile when the alternative is as immediately severe as drowning?
Worse, evolution clearly can get around this, dolphins have a trick that lets them (air-breathing mammals living in water) be alert 24/7, so why didn't every other creature get that? What's the thing that dolphins fail to get, where the cost of its absence is only worthwhile when the alternative is as immediately severe as drowning?