Food production arose where there were many domesticable plants and animals in the natural environment and not where such plants and animals were absent. Diamond points out that hunter-gatherers would not have put aside their lifestyles and taken up full-time farming unless they had access to a package of plants and animals that would, in combination, make food production a better lifestyle than hunting and gathering. In some places, the package of available plants and animals was simply less viable for farmers. To prove this point, Diamond contrasts Southwest Asia’s Fertile Crescent with two regions that developed agriculture later: New Guinea and the eastern United States.

The Fertile Crescent was probably the earliest civilization that had cities, written language, and widespread empires. According to Diamond, all of these were dependant on the ability of the people to grow and store food. Compared to other areas, the Fertile Crescent was unusually good for early food producers. Even before agriculture, the area’s Mediterranean climate produced a great deal of food per acre. The wild ancestors of wheat and barley were quite easy to domesticate and easily worth gathering for hunter-gatherers. These grains are very different from teosinte, the ancestor of the New World’s corn, which was of dubious value to hunter-gatherers and had to change a great deal before it would have become a useful crop. Furthermore, an unusually large number of the Fertile Crescent’s pants were self-pollinating, which made it easy to predict which plants would produce useful offspring. Finally, wheat had a higher protein content than either Asia’s rice or the New World’s teosinte.

Western Eurasia, the Fertile Crescent, southern Europe, and northern Africa have a climate that is highly productive for growing food. Agriculture did not arise spontaneously in the world’s other zones of Mediterranean climate, because those areas did not have the same advantages as western Eurasia did. Western Eurasia had a more diverse array of plants, especially of productive annuals that proved easy to domesticate. Eurasia had thirty-two species of large-seeded grasses, for example, whereas the other Mediterranean climates each had one, two, or none at all. Western Eurasia also had a greater variety of elevations, which produced plants that matured at different times. This provided a great advantage for farmers, who could bring mountain plants into valleys and capitalize on their fast growing times and drought tolerance. Because of the size and diversity of Western Eurasia’s climate, early food producers also had access to an unusually large number of big mammals. The ancestors of goats, sheep, pigs, and cows all existed in the Fertile Crescent, whereas the world’s other Mediterranean climates had few or no mammals suitable for domestication.

The product of all this was an agricultural package that included three major grains, four protein-rich legumes, four domestic mammals, and flax for edible oil and weaving fiber. Over time, people began to use animals for wool, milk, and work in addition to meat. Food production provided all the nutrients people needed as well as clothing and transportation. Also, compared to farmers elsewhere, the Fertile Crescent’s farmers faced less competition from hunter-gatherers.

Next Diamond turns to a description of the food-production packages that arose in New Guinea and the eastern United States. He explains that both packages were less viable, in comparison to hunting and gathering, than was the package in the Fertile Crescent. He points out that the difference cannot be explained by any lack of knowledge or ability in the people of those areas. Ethnographic studies have shown that people in hunter-gatherer societies typically know and understand the uses of virtually all plant and animal species in their environments. It is probable that the early farmers of the eastern United States and New Guinea knew all of the edible plants in their region and chose the best possible candidates for domestication.

In New Guinea, hunting and gathering is a marginal lifestyle because wild game is relatively unavailable. Because of this, there was a strong pressure to develop food production techniques, and New Guineans appear to have done this around 7000 BCE. Archaeologists are not sure which plants New Guineans domesticated first, but when Europeans arrived, they found people growing sugarcane, bananas, nuts, two kinds of taro, breadfruit, yams, and various herbs and vegetables. No grains were developed because no large-seeded grasses existed there. Similarly, no large mammal species were available for domestication. Overall, early New Guinean farmers had a food package that was severely lacking in protein. Pigs, chickens, and dogs were eventually brought from Southeast Asia, and the New Guineans adopted them. However, their environment gave them nowhere near as many advantages as the Fertile Crescent.

Native Americans in the river valleys of today’s eastern United States invented agriculture probably between 2500 and 1500 BCE. They grew squash, sunflowers, sumpweed, and a kind of spinach. These plants were not nearly enough to live on, so they only supplemented their diet until sometime between 500 and 200 BCE, when three more crops—knotweed, maygrass, and little barley—were brought into cultivation. All of these crops were high in protein, and some were high in oil. However, they have low production yields, and sumpweed can cause allergic reactions. In all, the available agricultural package did not supply all of the people’s needs until beans and a variety of corn arrived from Mexico around 200 CE. At that time, the local farmers lessened or completely abandoned their cultivation of the other, less productive crops. Their population expanded, and they created the largest towns and most complex prehistoric society in pre-Columbian North America north of Mexico.

The Fertile Crescent was, far and away, the best location in the world for the creation of indigenous food production. This left the inhabitants of the Fertile Crescent with higher populations, better technology, more complex social organization, and more diseases than people in other areas. Other areas had less viable packages, and Diamond believes that the areas where agriculture never arose had the worst array of domesticable species overall. He takes pains, however, to point out that those areas might have developed agriculture eventually if they had not first been colonized by European explorers.