Just a simplified 'follow-up' from my last reply!!!...
Here in Australia, our 'History' only goes back to my 'Great Grand Father". While in England, and Ireland, I visited locations/buildings
dated back to 'B.C.' and beyond... 'We' (Aussies) do not have that type of history. And it was amazing to see the types of structures,
some still waterproof today, that were built so long ago, by people with very limited abilities & tools... It puts things into perspective!!
Thousands of years ago, many races throughout many regions, understood about 'seeds' and crop growing,... yet not all...
'Others', were 'nomadic', meaning that they traversed the country-side indefinitely, without any such knowledge/desire. Local depletion?,
then just move on... Never built with stones. Never 'wrote' as such. Never changed... When i was a kid... (nope, I'm going no further)