"Sleeping animals are incredibly vulnerable to attacks, with no obvious benefit to make up for it — at best, they waste precious hours that could be used finding food or seducing a mate; at worst, they could get eaten."
It seems pretty obvious that sleep had an evolutionary advantage to conserve energy when the species couldn't be productive. For example, human sleep during the night because we can't forage / hunt / find a mate during the night because our vision requires light.
It seems pretty obvious that sleep had an evolutionary advantage to conserve energy when the species couldn't be productive. For example, human sleep during the night because we can't forage / hunt / find a mate during the night because our vision requires light.