In Guns, Germs and Steel, Jared Diamond makes a compelling argument that the current dominance of European cultures around the globe was predominantly determined by environmental variables.
The key to Diamond’s theory is that varying plant and animal domestication, growth in population densities and its correlating development of writing and the diffusion of ideas, as well as the rise of epidemic germs all confluenced to provide Eurasian peoples with a distinct environmental advantage.
Interestingly, the title is a bit of a misnomer: guns and steel are hardly discussed, but are merely references to the end result of the following factors (see Figure 4.1 on page 87) of human evolution:
- land mass orientation
- suitable wild species, ease of spreading species
- plant and animal domestication
- food surpluses and storage
- large, dense, sedentary, stratified societies
- political organizations
- epidemic diseases
Land Mass Orientation
Looking at a globe, you’ll notice that Eurasia is a large land mass that stretches east to west, while the Americas and Africa stretch roughly north to south. The significance of the east-west axis lies in the mobility of wild plants and animals in like climates.
Suitable wild species, Ease of spreading
Eurasia saw a cornucopia of wild plants and animals suitable for domestication. New crops or herds that succeeded in one end could spread all the way across to the other end. For reasons unexplained, large animals became extinct in the Americas. Africa has lots of large animals that have mostly proven unsuitable for domestication.
Plant and animal domestication
Domestication occurred thru accident and observation. Humans could domesticate plants while remaining nomadic, but once animals were domesticated, humans settled down. Domestication invariably alters the genetic makeup of plants and animals.
Food surpluses and storage
Once humans turned from hunter-gathering to farming and animal husbandry, surpluses lead to developments in storage, which normalized sustenance across extreme environmental variations.
With more than enough food, populations could diversify to include craftsman, bureaucrats, soldiers, and chiefs. Sedentary life also increases birth rates over nomadic life, which further increases population densities.
Sedentary life also meant that humans could experiment more, and thus technology developments sharply increased.
As the population densities grew, strained resources led some societies to attack and control other groups of humans, creating larger and larger political organizations.
Many societies developed writing as a means to more efficient administration, but writing also increased a society’s knowledge base, which became a clear advantage over societies that had no asynchronous knowledge transfer.
The increased density of humans and animals meant that more diseases were spread among humans and from animals to humans. Some of these diseases could quickly decimate a society, but those who survived would pass on their immune genetics as well as dormant strains of those diseases.