This book does a great job of explaining the complexity of human society as well as how much of a role the environment played in its development.

I cannot stress how important the role the environment played in the development of early human civilization. Our environment directly determines how we live and what we can do in a specified area. The Fertile Crescent (present day Turkey, Iran, Iraq, Syria, etc.) is where everything took off. This area contained a high diversity of crops and animals that humans were able to utilize. Diamond writes:

“The Fertile Crescent portion, possessed at least five advantages over other Mediterranean zones. First, western Eurasia has by far the world’s largest zone of Mediterranean climate. As a result, it has a high diversity of wild plant and animal species, higher than in the comparatively tiny Mediterranean zones of southwestern Australia and Chile. Second, Western Eurasia experiences the greatest climatic variation from season to season and year to year. That variation favored the evolution, among the flora, of an especially high percentage of annual plants. Among the world’s thousands of wild grass species, out of the 56 with the largest seeds, the cream of nature’s crop, virtually all of them are native to Mediterranean zones and overwhelmingly concentrated in the Fertile Crescent (32/56).”

So why the Fertile Crescent and not other areas along the Mediterranean zone? The first birthplace of homo sapiens has been determined to be in Ethiopia. The migration out of Ethiopia went north, and the Fertile Crescent was the first habitable location for human civilization.

Having an abundance of food allowed groups/tribes to shift from hunter-gathers to sedentary food-producers. A sedentary society gives rise to larger populations and higher population densities. Sedentary societies rely on a portion of the populace to produce enough food for everyone, while the remaining portion are free to explore other endeavors, such as becoming priests, scientists, bureaucrats, philosophers, etc. The human brain feeds on curiosity, and liberating more of them to study other facets of life, deepened human knowledge. So why didn’t all hunter-gathers become sedentary food-producers?

For one, many areas just did not have crops useful to humans. Consider this map when reading the following excerpt:

“The answer depends partly on the east-west axis of Eurasia. Localities distributed east and west of each other at the same latitude share exactly the same day length and its seasonal variations. For example, Portugal, northern Iran, and Japan all located at about the same latitude but lying successively 4,000 miles east or west of each other are more similar to each other in climate than each is to a location lying even a mere 1,000 miles due south.”

Now humans are smart, but we love copying each other. If the Fertile Crescent is considered the birthplace of the development of human society then you can see how ideas and crops could travel east and west, and north and south (to a limited extent) via trade routes. Now think about Africa. There’s a huge desert that runs through Africa, followed by a jungle, and then you get back to a Mediterranean-like zone. How would crops and domesticated animals travel that distance during those times? Very, very, very slowly. It’s important to keep in mind the contemporary tools and technology available during this time.

I also found it interesting the explanation Diamond gives for how modern food production arose. Diamond writes:

“The early unconscious stages of crop evolution from wild plants consisted of plants evolving in ways that attracted humans to eat and disperse their fruit without yet intentionally growing them … As parts of the fruit that we actually take into our mouths, strawberry seeds are tiny and inevitably swallowed and defecated, but other seeds are large enough to be spat out. Thus, our spittoons and garbage dumps joined our latrines to form the first agricultural research laboratories … At whichever such “lab” the seeds ended up, they tended to come from only certain individuals of edible plants – namely, those that we preferred to eat for one reason or another. From your berry-picking days, you know that you select particular berries or berry bushes. Eventually, when the first farmers began to sow seeds deliberately, they would inevitably sow those from the plants they had chosen to gather, even though they didn’t understand the genetic principle that big berries have seeds likely to grow into bushes yielding more big berries … You prefer large berries, because it’s not worth your while to get sunburned and mosquito bitten for some lousy little berries. That provides part of the explanation why many crop plants have much bigger fruits than their wild ancestors do.”

The germs carried by Europeans that were so devastating for the newly encountered areas came predominately from the domesticated animals Europeans had adopted from the Fertile Crescent. Many of the animals in the Americas and in Africa were not capable of being domesticated and thus, the people in these areas were never exposed to these diseases and as a result susceptible to them.

There’s no way I could ever do a proper review of a 440 page book, but I hope this has provided a glimpse. This book also does a good job of bringing it all home and showing how the Fertile Crescent lost its influence in the world by committing ecological suicide. If we commit ecological suicide on a global scale, we’re all in trouble.