Prologue
The first sentence in the prologue caught my inseparable attention. I figured I was about to read what was meant to provide a summary of Diamond's scientific reasoning. Diamond analyzed many different answers—ideas that could have ignorantly complicated Yali's question. He also provided his own opinion on these ideas and how obscure modern methods to determine the favorable answer were. The prologue seemed to explain that to answer Yali's question, you have to understand the geography of humans as they grew.

1 - Up to the Starting Line
Diamond tells us that four million humans, upright humans appeared. Then he told us that around fifty-thousand years ago, tools of stone and mass expansion of the human race occurred almost simultaneously. He went on to explain that this is probably why many mammalian extinctions had happened at the same time. It makes sense that humans would hunt down large sources of food to greater fund their spread across the globe. This chapter stimulated the idea that humans were able to expand because of the access to other continents because of dry land, watercraft, and access to food.

2 - A Natural Experiment of History
This chapter tells us about the invasion on the Moriori people in 1835. During that time, the differences between the Moriori and Maori proved fatal for the Moriori. The Maori had advanced weapons such as axes. The Morori that survived cut their loses and migrated into other islands. This chapter told us that the structure of an environment (and therefore the availability to resources) dictates the social structure of a species.

4 - Farmer Power
There are two fashions in this world: domestication and hunting. If you hunt, the chances of success vary and hunted supplies are usually used immediately. If you hunt, you can only support so many people at a time. If you decide to farm, however, your rates of success rise and stabilize exponentially. You can control a wider range of factors such as water and protection. If you farm, you are able to create much more food than needed and therefor get a surplus of supplies. Once you have more than you can handle, you being capturing meat like cows and chicken. Now you can feed your family, your livestock, your governors, and everything else in between. You can also support a very large population.


6 - To Farm or Not to Farm
In this chapter we learn that there was a long transitional stage between hunter-gatherers and farmers. Many civilizations adopted farming techniques at different times than others, and some civilizations abandoned the idea after witnessing other civilizations use it. The idea here is that both farming and hunting/gathering are two unalloyed ways of obtaining food, but farming eventually defeated hunting and gathering as the most safe and productive. Reasons for this are explained in “Farmer Power.”


9 - Zebras, Unhappy Marriages, and the Anna Karenina Principle
Expanding on domestication, this chapter explains that livestock and utility animals were unevenly spread out as countries grew. Every animal has some unique characteristic, either cosmetically or productively. This means that you can obtain plenty of meat and milk from large yaks, but not utilize the destructive rage of a zebra. Furthermore you may even see places with entirely new animals that are too dangerous to domesticate. This can help explain why some counties with tasty beef and large Oxen developed faster that another country that had only Cheetahs on the run.

10 - Spacious Skies and Tilted Axes
This slightly unpatriotic chapter tells us that movement is all in the location. Plants, animals, and even ideas dissipate easily into similar and easily accessible landmasses. For example, some plants that grow well in climates and soils in Africa may not be able to thrive in France. The terrain is also a hard thing to overcome. Very oddly shaped countries can be as wide as several thousand miles to just under the width of a football field. Lastly, the latitudinal position of an area affects the distribution of weather across an area.

11 - Lethal Gift or Livestock
In this chapter we come to solstice in the idea that laziness and death comes from adaptation. More specifically put, germs develop from our ways of infrastructure. As population grows with the power of livestock, we lose space and begin to compact. Humans then tend to still into calm lives. Eventually, our sewage begins to poison the environment. Even more dangerous is, if an unwanted animal such as the bubonic rat is introduced, the risk of a pandemic. Germs spread easily, and the density of civilizations can make extinction swift.



12 - Blueprints and Borrowed Letters
In this chapter we finally move deeper into culture. The methods of expressing language are discussed here, as well as how some languages came to be. There are three important writing systems: Alphabets, Logograms, and Syllabaries. Alphabet is a system in which many characters represent certain sounds and many of these symbols can be put together. Logograms have characters as well, but each is independent and doesn't mix. Syllabaries have characters specifically for syllables which are put together. Having writing systems like these allow civilizations to keep stable records and maintain assets.

13 - Necessity's Mother
Beyond language, this chapter talks about various technologies humans have come to develop. Large-scale inventions such as trains and engines, to the more common digital tools like software and supporting hardware, are what helped civilizations outgrow native compartments and become stronger. Using things like vehicles, people and their belongings can travel vast and harsh terrain faster and more efficiently. Using computers we can create automatic adding machines to spit out usable data from just a few figures instantaneously.

Epilogue
In the Epilogue we skip ahead into a summary of Jared Diamond's answer. He tells us that domestication, technology, landscape, and choice are what caused some civilizations to develop faster than others. Being able to append to demand, work through processes faster, move goods, and make decisions enables a civilization to nourish expansion. Diamond ends with a thought about the nature of researching this topic. He describes the difficulty of extracting accurate answers from a field of science commonly shrouded in stereotypes.