I made this discovery in New Zealand. The indigenous people of North Island enjoyed a climate that allowed them to grow the traditional Polynesian crops they were used to. But on chilly South Island the tribes - identical ancestry - could not grow enough of the foods they were used to to survive. They did, however, own the supply of jade, prized on both islands.
So did a trade of food for jade develop? Nope: the North Islanders, being short of protein in a country with no native animals whatever, simply added a new item to their diets - South Islanders. They're what's for dinner!
I am not one bit sorry this culture was wiped out. Hurray for Spain!