Life on Earth sleeps, due to many factors not present on other worlds where life that has evolved does not necessarily sleep. What are these factors,
and how does life that developed elsewhere cope without sleep? Almost all worlds that evolve life rotate, as rotation occurs in planets with liquid or
molten cores, which are warm and not cold, a requirement for life. Thus, these worlds have a night and day, and a night alone does not dictate the need
for sleep. The factor on Earth that nudged evolving life into regular sleep is the carnivores, huge and voracious and savage. Where today you have big
cats and wolf packs and large bears and sharks in the oceans, in the past life on Earth was more precarious. Look to the age of the dinosaurs, T-Rex
and the Saber Tooth Tiger. Life that was not a carnivore could expect a short and not too sweet life, on the run, relying on mass production of eggs or
young in order to perpetrate the species. Like vegetation that produces huge numbers of seed so that some plants could grow past the point where they
might be eaten, and bear new seed, non-carnivore species had little hope of continuing unless they did this. However, beyond the hoofed herds that
could outrun or form a circle to ward off the attacks, and thus could perpetrate themselves, and beyond bugs that multiply easily with mass laying of
eggs, there was yet another evolutionary technique that allowed survival - sleep.
As Darwin has pointed out, those features that survived passed on to the next generation. Those creatures that crawled into crevices and slept escaped notice of carnivores during the dark periods when a sense of smell could allow a carnivore to locate a meal, and lack of sight would prevent an easy escape for the meal. A sleeping creature is quiet, passes the time without being restless, and conserves energy. It simply developed that sleep was a positive evolutionary technique, and these genes passed even to carnivores due to the branching trees of evolution not being a straight line, but criss-crossing. Today's meal can become tomorrows carnivore, via evolution. Evolution then took advantage of the sleep state, likewise benefiting those creatures so they evolved. The creature who was highly alert during wake states was more likely to:
- get their own meals,
- avoid being eaten,
- find a mate and
- keep their young close at hand and safe.
The creature who was slow during wake states would conversely:
- get eaten,
- not propagate,
- not rear young.
In order to be highly alert during the day, the body then needs to do certain functions during sleep. It is not that the evolving body decides to do this, it
is that those bodies that mutate and do this are selected by success to spread their genes about. What processes does a body need to do, that could be
put off until sleep state? Sorting out the events of the day, in the brain, is one such process. Physiological functions are done during sleep also, like
kidney or liver or digestion, but this type of function creates little interest in curious man, who wonders, rather, about their dreams.
Oversleeping, the desire to escape, leaves man sluggish. The body has learned to adapt to sleep, doing physiological functions during this time. It is expected, by the body, that a matching wake state will be in place, so does not always have a dial to stop the sleep state functions if oversleeping occurs. Thus, lack of sleep, or too much, can create chemical imbalances in the body, so the body does not feel well. The giant hominoids on the 12th Planet do not sleep, as we have mentioned, but go into rest states. As can be discerned from looking at the shape of their heads, long and narrow rather than round as are humans, they did not have the same evolution. Mankind was engineered to survive on Earth, and some of the engineers created separate brains, the subconscious and conscious, which are physically separate brains. These giant hominoids do not have this separation, but likewise are more slow and less alert than many jittery men. Should you associate with them on a daily basis, this would be noted.