Today we will go over Chapter 11; we are reading one chapter a week.
I encourage this to be slow blogging - the very opposite of "breaking". I will leave this on my hot list for a week, so comment any time during the week.
When we get near the end of GGS, I'll start a poll for the next book; I am strongly leaning towards the book Ideas: A history of thought from fire to Freud.
Ground rules: I expect vigorous discussion. But I expect civil discussion. A sign I saw in a restaurant said
Be nice or leave
Chapter 11 is the first in Part 3, which is entitled "From food to guns, germs, and steel". Earlier chapters traced how food production arose is a few areas and spread, at different rates, to other places. This Part begins to show how this change in food production led to the Eurasians getting the guns, germs and steel, which, in turn, led to the answer to Yali's question about why they had all the 'stuff'.
When farmers meet hunter gatherers, Diamond points out, the farmers "tend to breathe nastier germs, to own better weapons and aror, to own more powerful technology in general, and to live under centralized governments with literate elites better able to wage wars of conquest".
Chapter 11 is about why farmers tend to have nastier germs.
Diamond first goes briefly over some of the ways germs spread themselves, illustrating with diseases such as trichonosis (which has to be ingested), to those transmitted by insects (malaria, plague, typhus, sleeping sickness), to those which modify the host to make spread easier (syphillis), to those which cause the host to help spread the disease (flu, cold, pertussis, cholera).
He also notes that microbes evolve more quickly than do the hosts, since they have shorter lifespans.
He then explains why many diseases occur as epidemics; such diseases tend to have several characteristics in common: 1) They spread effectively from an infected person to a healthy one. 2) They are acute rather than chronic - you either recover or die. 3) Those who recover become immune and 4) They are mostly restricted to humans. This makes these diseases "crowd diseases". A disease cannot spread from person to person if people aren't in close contact on a regular basis.
How does all this relate to the central thesis? Here's how:
First, because farming and raising livestock allows denser populations, it allows the spread of disease in ways that hunting and gathering does not. But the populations then become immune (either in whole or part) to the illness. When they meet up with peoples who do not share that immunity, the latter group is devastated.
Second, agricultural societies are not transient, so they live amid their own sewage. Indeed, many use that sewage as fertilizer.
Third, in agricultural societies many people live close to animals, and we get a lot of diseases from animals.
There is, of course, a lot more detail in the chapter, but I think I've gotten the gist.
Have fun in the comments!