>Yes you are right, there were MULTIPLE soveriegn tribes that did that.
No, there were none that have done that. There is no civilization that has lasted thousands of years, let alone some tribe.
>Interesting assumption there chap.
Not an assumption at all. Without writing, there was absolutely no useful way to preserve knowledge for any long period of time. Best you have are traditions and stories, which are lossy at best and easily wiped out by conflict.
>"Crap agricultural skills"? Good lord. Americans are the ones with "crap agricultural skills."
If it weren't for the agricultural technology and skills enabled by the scientific institutions of the "colonizers", we would still be having our children starving to death during droughts like the tribes and the early settlers. If it weren't for that technology, there wouldn't be enough farm land to feed all of the humans on the planet.
If it weren't for the "colonizers", tribes would still be murdering each other over territory during droughts, dying from simple diseases, suffering from malnutrition, living in terrible shelter, etc.
If tribes really were go great back then, none of the Native American reservations would be using any modern technology and people would be clamoring to join them and learn their ways.