Imagine that there were no usable fossil fuels, so the industrial revolution was impossible to start. Also imagine that useful metals close to earth's surface were several times rarer than they are today, so even entering the bronze age is much more of a challenge.How does this affect human evolution? Do we stay as we are - a mere single cosmopolitan species with moderate morphological variation, or do geographically isolated humans start to develop into new species? What kind of adaptations could be expected in different populations and environments?
>>16830320Early homos (lol) speciated quite a bit. But somo sapiens also spent around 290 thousand years as hunter gathers without speciating, so we wouldn't have speciated in the 10k years up until present. Natural selection pressure would definitely still be present, as well as genetic drift within separate populations. So if we remained hunter gathers after we spread out then I am pretty confident we would have speciated, over the course of hundreds of thousands/millions of years.So the question is is it possible to develop civilization without metal work. The best we could probably get is Aztec level. So no global trade, commercial agriculture, scientific revolution. I would think we would speciate within 2 million years.
>>16830327Where do you think the speciation will occur? You need isolated populations without much gene transfer for that, so I’d guess that Eurasia will have one, Australia another, Saharan Africa another, the Americas another, with maybe a few others popping up here and there in various places
