Zalameda

Zalameda t1_j9g4kej wrote

Every characteristics and features of every lifeform are kept because somehow, at some point, it gave the species members who developed it advantages over the members without such characteristics and features, thus these members are more able to survive, reproduce and pass on it's advantageous coding to further generations. This is evolutionary pressure and natural selection.
Applying this to dreaming, we can hypothesize that dreaming emerged from a variation in the way the brain was hard-wired by the genes that dictate it's development and features throughout the species's member's lifespan; and that dreaming reinforces vital synaptic connections that would go into atrophy in members who were uncapable of dreaming, thus making dreamers brain healthier.
While most dreams make absolutely no sense, it still brings elements of waking experiences, as no one can ever dream of something not experienced in waking state of consciousness. As a vague example, you can't dream of someone with a face you have never seen. If you dream of an unseen face, it will at least be a combination of facial features of people you have seen.

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