Provide specific examples in Chapter 8 to explain Diamond's argument that the people who lived in a specific area did not determine how successful domestic agriculture would be in that area.

In Chapter 8, Diamond explains that while there are over 200,000 species of wild flowering plants, very few of them are fit for crop development. He examines three regions--the Fertile Crescent, New Guinea, and the Eastern U.S. to show that people who lived in a region weren't the major determinants of how successful domestic agriculture was in that area.
The Fertile Crescent became a center of agriculture in part because so many of the crops there are productive in the wild. The germination of their seeds occurred naturally, as soon as people began to cultivate them. In addition, many of the plants in this area are self-pollinating. This situation is very different in Mesoamerica, where there were far fewer domesticated animals to provide meat and where the staple crop, corn, was far more difficult to grow than the crops in the Fertile Crescent. Diamond also mentions New Guinea, where the naturally growing crops were also less productive; the region lacked cereal crops because there were no starting grass crops that grow there naturally. In addition, there were few candidates in the eastern U.S., as Diamond explains, to develop into major crops. Therefore, the people who live in a particular geographic area were not the major determinants of whether domestic agriculture would be successful; instead, the crops that grow there naturally were the major determinants.