In Parts II and III of Guns, Germs and Steel, discuss Diamond's presentation of the "systems of production."
One of the key elements that led some nations to develop and advance quicker than others, Diamond argues, resulted from their system of food production. Historically, for the majority of man's history, man has been reliant on the hunter-gatherer lifestyle. It is only very recently, comparartively, that some groups began to move towards a system of food production that is defined as follows:
...domesticating wild animals and plants and eating the resulting livestock and crops. Today, most people on Earth consume food that they produced themselves or that someone else produced for them.
What is so key about the rise of food production is that it allowed populations to be exposed to diseases from the animals that they began to use in their food production that gave them immunity. A shift from the hunter-gathering to farming also meant much more concentrated volumes of food, which in turn allowed for much greater and denser populations, giving such groups much more strength in terms of numbers and allowing systems of government to emerge. Food production is one of the key components that answer Yali's question posed in the opening chapter about why some nations advanced quicker than others.