How are "problems of the modern world" related to Yali's original question?

Diamond explains that "much of Africa is still struggling with its legacies from recent colonialism" (p. 16), just as Yali’s question refers to differences between New Guineans and those who colonized them. Diamond goes on to cite several other parts of the world, including "Central America, Mexico, Peru, New Caledonia, the former Soviet Union, and parts of Indonesia" where "indigenous populations" struggle with the domination of their conquerors’ descendants or their past "collisions" (p. 16).