The evolution of man’s dreaming reaches way back into the evolutionary mammalian past. Researchers accept evidence that dogs have dreams. Any explanation of the evolutionary, initial ratification/benefit must have, at base, a simple justification. So why did this remarkable facility evolve? Let us imagine how it helped the earliest humans.

Disclaimer – When I first formulated this theory, I fell into the self-centered trap of “if this theory is true then other conjectures must be false”. On reflection, I realized this is an A OR B trap/falicy as opposed to A AND B. I think my theory is very basic in terms of early development and evolutionary ratification of survival benefit. It can even be applied to other mammals like dogs. When I later thought about other dream effects/motifs like broad, non-specific  anxiety, I have to admit it does not directly fit my model presented below of specific danger-avoidance and attraction to better opportunity. I should know enough to understand that the Evolutionary System ratifies on the basis of the sum total of all outcomes that are supportive.

Dreaming and nightmares as a necessary repetition mechanism to establish deep association for avoidance of danger.

This is my explanation of the initial, basic and continuing mechanism and evolutionary ratification that I present here. I think the easiest explanation can be seen in a scenario:

.A carefree juvenile is being warned to stay away from the high grass but like any youngster the communication may be clear but the urgency is not there. It does not compete with his short attention span, and immersion in play. The focus of juveniles at play is very narrow. Initially, he does not even see the proximity of the high grass.

He hears a muffled grunt. He smells a meaty smell. He looks up and sees high grass very close. His parents have been acting concerned and motioning and verbalizing the young ones to stay closer. He notices the adults stiffen and sniff the air. Strange, escalating verbalizations come from them and he can see the whites of their eyes. They begin to look like children he has seen that were frightened.  Normally his troupe does not go near high grass. He wonders what all this means. He does not have an immediate, automatic reaction so he is frozen in place.

Suddenly everyone is screaming wildly. He has never seen every adult in the extreme of complete panic – this is terrifying.  A monstrous animal leaps from the tall grass and seizes another child of the group who screams piteously. – Blood and panic. His mother runs to him and grabs him, almost dislocating his shoulder as she yanks him and runs away. He is frozen and traumatized.

Rhetorical question: Will this juvenile dream about this that night and on subsequent nights? Of course – he will have many, many nightmares. These nightmares are very common in young people. They are also almost inevitable after episodes of extreme stress at any age.  Will not all these associations be cooked in at a low level in his consciousness?

Why constant dreams/nightmares? Memory, learning and deep association can only be effective by direct and intense repetition. The research I see now, is emphatic on the role of repetition. This mechanism is necessary down to the biological/chemical process at the synaptic level. The most effective system of association and priorities is dependent on repetition. It is like a system of game trails where the most trod path is dominant and there are many lesser branches. The alternative would be real-world, sporadic repetition of near-death experiences until the person is dead or more alert. This is not the best survival path. How do we get the repetition? Dreaming.

By the repetition in dreams,all these important associations and reactions are intensified. The next time he is carefree (maybe never to the same degree as before) and absorbed in the immediate but smells that meaty smell or sees the adults get still or sees that look or he hears those peculiar noises from them or gets too close to the high grass or hears that grunt, or adult alarm cries- will not his attention be automatically riveted and Adrenalin flow – a start and flight reaction?  Won’t he start running towards the adults and safety? Is this not a survival trait? The trigger that acts past the state of immediate absorption is a monitor – observer. This would be the main ratification and driver of this the unique dream state that is, otherwise, a drain on energy resources. I think it is the main reason for dreaming to evolve going way back to other mammals that dream. This does not exclude other theories. 

Most times the conscious mind (left-dominant) must be rooted in the expected and absorbed in the immediate, whether it is food gathering and especially in play. The hidden observer can compare with past associations and trigger a mental tap on the shoulder. Dreaming sets up the associations after the remains of the day are relived and re-hashed. Things that the left brain in the Usual State of Consciousness is willing to ignore or deny are associated and relived with new intensity and re-tuned with the glandular responses. The chemical process of deepening synaptic paths continues. An ordinary memory string can be triggered by a connection starting point like a picture, a poem or a song. The above memory links are more like alarm triggers. 

We could consider Post Traumatic Stress Syndrome as a more extreme effect of this mechanism.

I have received all of these pieces from others in articles. I just put them together in a good guess. I fail to see the harm and thank you for your indulgence.