Well, here are some of my thoughts after completing this book:
GUNS, GERMS AND STEEL is a book that was highly criticized for being environmentally deterministic as it is mainly about the impact that the environment had on factors such as food productions, fighting skills, technology, political organizations and language/writing skills for the development of human societies. Some evolving faster than others.
One of the main questions the author attempts to explain is why Eurasian civilizations developed a more complex or organized society faster that civilizations in America or Africa and ended up conquering them instead of being the other way around. For example, why Pizarro conquered the Incas and Cortes the Aztec empire instead of them conquering the Spanish civilizations? What gave them such a head start before them?
The main argument defended throughout the book by the author is mainly that thanks to the horizontal east-west geographical axis of Eurasia is what favored such environmental conditions for developing the complexity of these societies in a shorter period of time than on those living in the vertical axis such as America or Africa. He gives far more importance to this geographical distribution rather than the intellectual or the inherited differences of human evolutionary biology or genetics. He argues that this North-South vertical axis in America has wider variety in latitude giving therefore big changes such as a variety in climate or areas such as the deserts or rainforest making it difficult for plants or animals to flourish, to domesticate and the diffusion on these new techniques and technology faster to closer societies.
According to Diamond, the first condition favored by this geographical distribution was food production. Through livestock and animal domestication, this allowed sedentary people such as farmers or herders to settle and achieve higher population densities than hunter gatherers which eventually were being replaced or had to end up adopting these new food production skills. The societies that adopted these new skills gave them a head start towards guns, germs and steel which basically means better weapons and that eventually helped them conquer other civilizations around the world.
He also uses Tolstoy's quote "Happy families are all alike; every unhappy family is unhappy in its own way" to make the Anna Karenina principle which he applies to animal domestication. By this principle he says that human and most animal species make an unhappy marriage, it is through factors such as animal's diet, growth rate or mating habits among other characteristics that some wild animals were better for domestication than others giving again Eurasia also the best candidates for this domestication. Was this the romantic side of Diamond??
By the way....Kuru is caused by a virus?!! I don't think so. Kuru, which is caused by cannibalism, as well as Creutzfeldt-Jacob, Fatal Familial Insomnia and the Mad Cow disease among others are caused by PRIONS not by a virus. They do transmit like a virus, but they are NOT viruses they are Prions! I do not know if he did it in order to avoid the complexity of the subject on Prions and just to give an idea to the reader. But on a book that is approaching the evolution of microorganisms and/or diseases and the impact is can have on an entire population such as smallpox had on the Native Americans during the Spanish conquest then this will be the right time to introduce prions and their impact of the practice of cannibalism. Stanley Prusiner received a Nobel for his research work on Prions if any reader is interested on this.
Now, Diamond tries to use Darwin in his favor stating that his first chapter On the Origin of Species he explains how domesticated plants and animals arose through Artificial selection by humans but what about the process of Natural selection in humans in all this history? We have evolved thanks that we are a very competitive species after all. Are we really only the result of all these environmental conditions that directed the fate of our societies? However, I think he does apply the process of natural selection regarding our immunity to certain microorganisms.
Personally I think, that yes environmental factors do play an important role in the development of a society but it is also thanks to the inherited traits of our evolution that give humans the ability to adapt to these conditions and use them intelligently according to our needs and our understanding. It has to be multifactorial not only geographical. Now, with the rise of Epigenetics it would be interesting to know how does the environment really have influenced and directed our gene expression and the new adaptations and/or mutations we have developed and are still developing.
Anyways, this is a great book on the "GUNS AND STEEL" part of world history and you can learn many interesting facts since the rise of our civilization. But it is fair regarding its approach on the"GERMS" part. He does mention how many epidemics have played a major role on the fate of many human societies throughout history (Influenza, Smallpox or HIV) and how this diseases are still influencing us through mutations in our genetic code and play an important part of our evolution. However, as a professor in geography, I think he focuses deeply on his geographical axis argument that make us who we are today. Well, if you follow the author's thoughts, after all it was Eurasia who took the lead and conquered and influenced many other parts of the world and our history and making him writing this book.