Recently I read an interesting book about history of human societies called “Guns, Germs and Steel”. The book tries to answer the following questions: “Why some societies ended up being more successful than others? Why, for example, Europeans from XVI century onwards invaded and replaced Native Americans, Aborigen Australians and not vice versa? Was it difference in people themselves or were there some other factors?”. And the short answer is environmental factors played huge role in giving some societies early head start and there was no evidence that some people’s characteristics were better than others.

The first and main factor that gave some societies more power than others was the rise of farming. Plant and animal domestication started in each continent at different periods (and did not start at all in some). It first started in the area that is now referred as Fertile Crescent which lays in current Middle East around 8500BC. It was followed by China in 7500BC, and these two areas can be regarded as the earliest sites for the onset of farming. However, it took 5000 more years for Native Americans to start domestication where they started around 3500BC. How societies with farming had more power over non-farmers, i.e. hunter-gatherers? The answer is that farming allowed humans to acquire more food than they can consume, so they had surplus. And that surplus resulted in population boom, because farmers led sedentary lifestyle as opposed to hunter-gatherers, therefore shortening birth cycles and there was more food available for more people. Moreover, that surplus allowed to have some people doing other job than farming, like craftsmen, bureaucracy, kings, soldiers, which resulted in more complex societies. Such societies could easily replace or drive out hunter-gatherers by both numbers and their technology.

Then why farming started in Eurasia first, and 5000 years later in America even though they both have similar Mediterranean like climate? Among all wild plants growing in the planet, only tiny fraction is edible. And not all edible plants can be domesticated. And from those which can be domesticated, the efficiency (calories per area of farming) differs greatly among each other. It turns out that Fertile Crescent had wild plants that could be easily domesticated and that gave more calories per given area than other continents. Fertile Crescent domesticated wheat, barley, peas, while China domesticated millet, rice, soybean. America did not have such wild productive plants, and people there domesticated corn, and some type of beans thousands of years later.

Similarly, animals were much more successfully domesticated in Eurasia compared to both America and Africa. Major five animals that were domesticated in Eurasia are sheep, goat, cow, pig, horse. In America only llama was domesticated and it did not became as widespread as major five animals in Eurasia. Surprisingly, in Africa none of animals were successfully domesticated, especially considering the fact that nowadays the most diverse animals live in Africa. It turns out that wild animals should have a set of certain characteristics to be successfully domesticated. And African mammals did not meet those requirements, but major five of Eurasia did.

Another factor that played role in quick spread of food production, inventions, writing in the continent is its orientation of its axes. America and Africa mainly stretches from North to South, thereby having North-South axis. In contrast, Eurasia has mainly East-West axis. How does it relate to spread of technologies? Related with food production, it appeared first in Fertile Crescent (8500BC) and then spread both east towards Central Asia, Indus Valley (6500BC) and west to North Africa, Europe (5400BC) quickly, mainly because it is easier to grow similar crops in similar climate zones. However, it took a much longer for Mexican crops such as corn and beans (3500BC) to spread north to eastern US (900AD), which has much smaller distance than between Fertile Crescent and Europe. In case of America there were environmental obstacles as well, such as Mexican desert and narrowness of Panama.

One more factor in determining the power of societies was, *surprise*, germs. As humans adopted farming and started living close to its waste and livestock, it was a perfect ground for development of germs. The germs from which nowadays every child get vaccinated, such as smallpox, flu, tuberculosis, malaria, cholera are all originated from animals and passed to people living close to those animals. Over thousands of years people in Eurasia got immune to these diseases, but for other people who never had these germs, it was lethal. For example, after Europeans started conquest in America in XV century 95% indigenous people of America died from germs brought by Europeans. It is astonishing fact that Europeans conquered most Native Americans mostly by germs rather than with the guns or other technology.

All these factors together played major role in dominance of some societies and disappearance or assimilation of others. Those who had early start in farming eventually developed kingdoms, guns, steel and conquered/replaced other societies.

I found so many interesting things in this book that I can highly recommend it to everyone. It is not another boring history book with plain history facts, but this takes systematic approach from very early hunter-gatherer times to modern ages.