Evolution: what were we doing for 100.000 years? [closed]

Question

I'm not a biologist/anthropologist but there is a question that comes up again and again and which I couldn't find any deeper thought, even not a speculation. As far as I understand it, according to modern evolutionary science, the anatomically modern Homo Sapiens Sapiens exists since about 100-300.000 years. Lets be conservative and take 100.000. However, human's ability to build a culture, a society, a civilization that uses the rational mind, an analytic thinking that gives birth to philosophies and, even more recently, to science and technology showed up only very late compared to the human's history. Lets say with the Sumer civilization about 3.000 BC. Now, this implies that, despite having anatomically a fully developed brain, for about 95.000 we were doing not much with our intelligence other than hunting, surviving, develop very rudimentary tools, migrate and not much more but without any cultural development which one should assume is proper of a human brain such as thinking, developing increasingly sophisticated tools, develop philosophies, religions, arts, music, sciences, math, technologies, etc. The latter even not much developed before the scientific and industrial revolution in the last few centuries.

This doesn't make much sense to me. One might argue people were busy with surviving, there was no education and we couldn't develop our IQ, there were no books for cultural transmission, etc. This might be part of the answer explaining a stop of cultural evolution for some centuries, even some thousand years, but for 100.000 Years? This doesn't look to be the fully picture.

So, my question is if there is something (article, book, etc.) of someone who pondered on this aspect in more detail? Is there a possible explanation why evolution produces a brain without using its full capacities for 95% of its existence so far? Are we 100% sure that the brain humans had 50.000 ago are the same we have nowadays?

Answer 1

I can think of two factors that could explain why a civilization took so long to appear despite humans having fully developed their capabilities.

1. Civilization is built into previous achievements: this generates an exponential growth in technologies making it easier to improve or create technologies giving that you already have the tools to create it. Think about a simple light bulb, how long it would take you to build one from scratch having to build any tool you use? Having this into account is not surprising that a fully articulated language could take thousands of years to be built from scratch.
2. Population size: 100-10K years ago the human population was a fraction of what it is now. This would slowdown civilization if we consider that development is proportional to the population.

Answer 2

The measures and reasons for the evolution of behavioural modernity https://en.wikipedia.org/wiki/Behavioral_modernity?wprov=sfla1 have generated many theories, like for the FOXP2 gene that works on human speech.

Biologically we can consider the evolution of crop species and their yields and docile livestock as a non-human evolutionary change which has massively boosted human culture into civilizations i.e. wheat, potato, corn, grape yields

If you study "the evolution of stone tools", there are theories of the full planning and workflow to shape difficult stones into fine craftmanship, which give an intuitive grasp of cultural and biological increments in technology. The crafted tools of humans changed gradually and radically over the last 70k years. That study doesnt overlap much with biology though, because of sparse biological evidence.

There are also mathematical formulas to chart the evolution of intelligence / noogenesis as a sum of the total synapses in many individuals communicating together, something that changed exponentially recently when humans made tribes of many thousands.

Tribal humanity becamy civilization. Aborigines and Maori and Papuans and tribal north Americans and Eskimo all represent different cultures of technologies and tribes.

There seems to be a synergy of many synapses communicating, when tribes group into civilized cultures of 1000ds of humans, further boosted by emergent technologies like agriculture, which is represented in indus valley/egyptian/mayan cities, which accelerates the technologies in a confusingly exponential way.