There were isolated tribes in NG and in South America, that had advanced far more in growing crops, farming animals and making hunting implements and had real cohesive family units right up to 80 years ago without any outside influence. A harsh isolated land mass ??, have you been to the Hunter region or anywhere on the Eastern Seaboard or Kimberlies. The seas rivers and land abounded with eatable life forms but 40,000 years of indigenous habitation only wiped out the easily caught mega fauna and destroyed thousand of hectares of forest with uncontrolled burning because they lacked the knowledge of sustainable living.
