The transition into the Neolithic Era is arguably the most important bit of our history.
As the Linguistics subforum Moderator, I would suggest that the development of spoken language is in that same category. It's likely that this occurred around 70KYA, because this is when archeologists and anthropologists see a sudden explosion of complex, coordinated activities that could not possibly have been performed by people who were using their hands for signaling at the same time.
The first successful migration out of Africa, into a new place with different food and dangers, occurred a few thousand years later.
Nomadic groups never stayed in an area long enough, or in large enough groups to collaborate their ideas and expressions.
Jean Auel studied what was known about Paleolithic communities exhaustively, as she prepared to write her "Earth's Children" series of novels, beginning with
Clan of the Cave Bear. She insists that Paleolithic tribes did indeed establish permanent home bases, generally caves, leaving a contingent of the elderly and lame to take care of the children, while the strong young men were out hunting.
Anthropologists say the evidence tells us that each clan established its own hunting/gathering territory, generally an area that a party could cover in a few weeks, then return home with all the food, skins, etc., that they could haul without wagons or draft animals. (The travois was a Paleolithic invention.) Since pre-agricultural communities had no way to create (much less store) any significant quantity of surplus food, during years of low rainfall (which occurred about every seven years) neighboring clans attacked each other in order to invade their territory. Paleolithic human fossils indicate that the lucky 20% who survived childhood typically lived into their mid-50s. Re-examining these skeletons with modern technology discovered the sad secret that the majority of them were killed by other humans. Apparently each tribe targeted the other's elders, since they were less able to defend themselves.
I can imagine a scene in which the warriors on both sides stop for a rest, and suddenly one yells, "Hey, the old folks on both sides are dead. There's probably enough food for all of us now. We'll be off now. See you at the summer festival next year."
With the advent of agriculture, people were able to stay in one area and cities began to form around them. . . .
Villages came first. Agriculture required people to give up their nomadic lifestyle and settle down to tend their crops and flocks. There are many things that sedentary people can do, which are impossible or impractical for nomads, such as building houses and inventing the technology of pottery--which is too fragile to carry on a hunting trip.
As their numbers increased, they would have noticed that larger communities benefit from
division of labor and
economies of scale, making them more prosperous and permitting new professions to arise, such as roofers, vintners, cobblers, traders, explorers, tinkerers and even musicians. This undoubtedly encouraged them to invite the (perhaps still Paleolithic) people in the next valley to come live with them and increase the prosperity of both tribes.
. . . . and with that the "Big 8 of Civilization."
The literal meaning of the word "civilization" is merely "the building of cities." A city is not just a large village. In a village, everyone knows everyone else, at least well enough to trust them and cooperate with them. As a village grows into a city, people no longer know everyone personally, so the binding force of kinship attenuates. One of the key features of a city is the creation of a formal government, since it is no longer practical for everybody to simply do what Grandpa says--especially since they don't all have the same Grandpa. One leader cannot keep the peace and adjudicate all disputes, so a hierarchy of command is established.
Another problem with villages that become cities is that business transactions become very complicated. John puts a new roof on Peter's house; Peter gives Oscar two gallons of wine; Oscar fixes the broken wheels on Mary's wagon; Mary plays the lute at Paul's birthday party; Paul makes shoes for John's baby. These people don't even all know each other, so how do they know that they've all gotten a fair deal?
They invent clever symbols to carve into clay tablets, indicating the relative values of their labor and products. Within a few generations, the symbols have become standardized and their use has spread to other facets of life.
And this, my friends, is the dawn of the technology of
written language!