Life evolved under conditions of light and darkness, light and then darkness. And so plants and animals developed their own internal clocks so that they would be ready for these changes in light. These are chemical clocks, and they're found in every known being that has two or more cells and in some that only have one cell.
Being unconscious is the ultimate disability.
Human enhancement is now being driven by military imperatives, at least in the US, because civilian society is more conservative in its approach. It’s a missed opportunity for a society-wide push to understand and reduce our need to power the brain down for hours every day. Every hour we sleep is an hour we are not working, finding mates, or teaching our children; if sleep does not have a vital adaptive function to pay for its staggering opportunity cost, it could be ‘the greatest mistake the evolutionary process ever made’.
