Thursday, September 21, 2006

Summary: "Guns, Germs, and Steel" by Jared Diamond

"Guns, Germs, and Steel" is one of those rare books that I think pretty much everyone needs to read--especially Westerners. It is a sizable book, and a bit of an undertaking, but even for people who probably won't get around to reading it, I think at the least that everyone should try to be familiar with the basic analysis Diamond puts forward.

Having just finished it for the second time (I rarely read the same book twice), I decided to make a basic outline of Diamond's arguments both for the benefit of others and so that I can refer back to it as I continue to study world history. I quote Diamond pretty liberally, so I hope I'm not violating any sort of copyright laws that are going to get me into trouble. If so, I'm sure someone will be kind enough to inform me ;)

People should also feel free to contact me if they have any questions about any aspects of this summary, or suggestions as to how it could be made more useful.

Otherwise, I hope to read "Collapse," a more recent work by Diamond, at some point. But if somebody out there has put together a summary similar to this one I'd sure like to check it out.


5-9 million years ago: "...a population of African apes broke up into several populations, one of which proceeded to evolve into modern gorillas, a second into the two modern chimps, and the third into humans."

Homo erectus, the 1st human ancestor to spread beyond Africa about 1-2 million years ago, had a similar body size to modern humans but about ½ our brain size

Homo sapiens date back about ½ million years; this also corresponds to human ancestors'’ earliest entry into Europe and the beginning of our use of fire

Homo neanderthalensis populated Europe and West Asia 40,000-130,000 years ago and were the first humans to leave behind strong evidence of burying their dead and caring for their sick

Cro-Magnon humans represent the "“Great Leap Forward"” in human evolution, taking place around 50,000 years ago; "...biologically and behaviorally modern humans."” Evidence of stone and bone multi-piece tools and weapons, jewelry, houses, sewn clothing, carefully buried skeletons, and artwork. Proposed explanations of the "“Great Leap"” include the perfection of the voice box, changes in brain organization, either/both of which could have enabled the development of modern language. These developments coincide w/ the "“extinction" of the Neanderthals and "...the first proven major extension of human geographic range since our ancestors'’ colonization of Eurasia."” This geographic extension, reaching in Australia and New Guinea, provides the first evidence in human history of the use of watercraft.

11,000 B.C. (note Diamond'’s distinction between "“calibrated"” and "“uncalibrated"” radiocarbon dates.): end of most recent Ice Age. All peoples on all continents were still hunter-gatherers, most still living in nomadic bands of no more than a few dozen members; corresponds to the beginnings of village life in some parts of the planet, the first undisputed peopling of the Americas, the "“Recent Era."” W/in 1500 or so years, humans will begin domesticating plants and animals in southwest Asia, then elsewhere. By way of contrast humans did not even begin entering the Americas (via Alaska) until 12,000 B.C. Earliest sites of plant/animal domestication correspond w/ earliest instances of what we now refer to as "“civilization."”

8,000-2,500 B.C.: all species for whose dates of domestication we have archaeological evidence were domesticated during this period, after which, there have been no significant additions

5,500 B.C.: the evolution of chiefdoms in the Fertile Crescent region (larger, more centralized organization w/ more complex economies than tribal configurations)

4,000 B.C.: the domestication of horses begins in the "“steppes north of the Black Sea."” This development would change the face of warfare all the way into the First World War.

>3,000 B.C.: first known independent invention of a writing system by the Sumerians of Mesopotamia; may also have been invented independently later by Chinese, Egyptians, and Mexican natives. All early writing societies were agrarian, socially stratified societies with complex and centralized political institutions. Writing was initially a tool of the ruling classes to facilitate the maintenance of their empires.

2,500-1,500 B.C.: eastern U.S. "“founder crops"” were domesticated during this period, though farming did not begin to supply a major part of the diet until around 500-200 B.C., and farming did not develop such that densely populated chiefdoms arose until >900 A.D.

1,000 B.C.: the evolution of chiefdoms in Mesoamerica and the Andes

2nd century B.C. China achieves significant political unification, and remains largely thus for the rest of its history (this unification will have significant effects on China as compared with Europe later on)

300-800 A.D.: Austronesians arrive on the African island of Madagascar after crossing 4,000 miles of Indian Ocean from modern-day Borneo (Indonesia). Diamond refers to this colonization as perhaps the single most astonishing fact of human geography. This fact is perhaps explained by a well-documented trade route that linked India w/ Indonesia to the east, and India to Egypt and the coast of East Africa to the west. This route was written about as early as 100 A.D., but is well-documented after 800 A.D.

Medieval Europe (500-1500 A.D.): beginnings of an Industrial Revolution based upon water and wind power; by late Medieval or Renaissance period, most of Eurasia had come under the rule of organized states, even empires

1500 A.D.: beginnings of European worldwide colonial expansion; peoples on different continents differed greatly in technology and political organization. Indigenous population of West Indies exceeded one million when Columbus arrived. The first European colony was founded on the American mainland around 1508, at the Isthmus of Panama, followed by the conquest of the Aztecs and Incas in 1519-1520 and 1532-33, respectively.

European "“superiority"”: some of the suggested primary reasons for Europe'’s advances include genetics, the stimulatory/inhibitory effects of cold/hot climates, and large-scale irrigation systems-->centralized bureaucracies; none of these explanations stand up to scrutiny however, according to Diamond

Human-animal co-evolution: the survival of megafauna, which existed on most all continents, into the modern era, depends largely upon how long these critters had co-evolved w/ proto-humans before being confronted by modern humans possessing fully developed hunting skills. E.g., Eurasia and Africa vs. Australia, New Guinea, and the Americas. Whether or not, and what kind, of megafauna were available to developing societies ended up making a pretty profound difference in the course of their evolution.

Other environmental factors that Diamond cites as being important in a society'’s evolution: climate (e.g., favorable Mediterranean climate), presence of plant species favorable to human cultivation, geological type, marine resources, area, terrain variety & geographic fragmentation, axis orientation (e.g., east-west vs. north-south), and isolation.

Axis orientation: "“Localities distributed east and west of each other at the same latitude share exactly the same day length and its seasonal variations. To a lesser degree, they also tend to share similar diseases, regimes of temperature and rainfall, and habitats or biomes (types of vegetation)...the germination, growth, and disease resistance of plants are adapted to precisely those features of climate."” This similarity of condition facilitated the spread of plants much more quickly east<-->west than north<-->south. With regard to the possibility of the axis direction also affecting the diffusion of technologies and ideas, Diamond notes "“In general, societies that engaged in intense exchanges of crops, livestock, and technologies related to food production were more likely to become involved in other exchanges as well."”

Isolation is an interesting variable, because, on the one hand, how long did a given society have to develop on its own before coming into interaction with other societies which might potentially conquer or contaminate it (e.g., 3,200 years for the Polynesians vs. 13,000 years for Native Americans)? On the other hand, there are some obvious, powerful benefits to interaction between societies, provided they don'’t conquer you. We might think of competing, or at least intermingling societies the same way we think of interactions between individual critters w/in a given species. It'’s the aggregate effect that'’s important from a historical perspective, not the effect on one of the individual societies; hence regardless of which individual societies have come out on top and which were assimilated/destroyed/plagued, the aggregate effect is that competition/interaction has tended to strengthen human society as contrasted with isolation.

Variation in environment--> variation in subsistence.

Subsistence methods--> population size/density:

There are probably less than 10 places on Earth where food production arose independently. By food production, we mean domestication of plants and animals--—i.e., taking control of a species'’ reproductive cycle such that we alter it genetically towards a form more useful to human beings. This sort of inter-species co-evolution has long existed in nature (e.g., "“ripe"” vs. sour fruits that attract animals only once the seed is fully-matured), domestication is simply more conscious and directed. This process began simply enough, w/ human hunter-gatherers tending to harvest fruits most pleasing (and convenient) to them, and hence disperse the seeds of those individual plants more widely.

With regards to animals, there are a few very important characteristics that determine whether or not a given species can be domesticated (and only a small fraction can): 1) lower on the food chain (i.e., no carnivores) for reasons of bio-efficiency, 2) fast growth rate (aids in selective breeding), 3) must be willing/able to breed in captivity, 4) not too nasty (e.g., bears and hippos), 5) not a "“nervous"” species (e.g., deer) that don'’t function well in captivity, 6) "“herd"” species rather than territorial.

Similarly w/ plants, only a fraction of the overall available species have been domesticated, and pretty much all of these were discovered and domesticated in ancient times.

Farming offers more calories available/acre; permits or requires people to adopt sedentary living; creates seasonally pulsed inputs of labor (making food producers available for other activities after harvest season); leads to a shortened birth interval (approx. two yrs for farmers vs. four for hunter-gatherers) because one doesn'’t have to wait for their child to be as old before they can safely have another; provides food surpluses that can be more easily stored w/in a settlement; food surpluses in turn allow for non-farming "“specialists"” (e.g., leaders/bureaucrats, soldiers) to devote less time to gathering food; additionally, domesticated animals provide food, fertilizer, fiber, labor/transportation, and acquired immunity to certain epidemic diseases.

[Interesting note on the evolution of monoculture farming: Diamond claims that monocultures developed in places where large animals were domesticated and could be hitched to plows, thereby tilling the fields and allowing for broadcast of a single type of seed. Alternately, in places where these animals weren'’t available, fields tended to be planted by hoe and stick, individually planted seeds, and a mix of species.]

Of course, not all of the "“benefits"” of farming would have been immediately recognizable to early farmers, and according to Diamond, some archaeologists have demonstrated that early farmers were perhaps less well-off than their hunter-gatherer contemporaries. [Note: not all ancient hunter-gatherers were nomadic, just as not all food producers were/are sedentary.] The transition from hunter-gatherer to farmer took place over thousands of years for the earliest farmers, and did not involve one big decision, but many smaller ones. What were the factors that contributed to this decision? 1) declining availability of wild food (e.g., megafauna extinctions); 2) climate changes which expanded the range of some domesticable plants; 3) development of improved technologies for collecting, processing, and storing wild foods; 4) availability of a suitable "“basket"” of potential domesticable plants/animals, such that farming begins to offer a reasonable alternative to hunting-gathering (see the global distribution of high quality, domesticable plants/animals in antiquity for a powerful hint at why farming began in some places and not in others)

There is also a correspondence between primary food-gathering technology and population density; i.e., hunter-gatherers-->less dense (e.g., 5 people/square mile), while farming-->more dense (e.g., 1100 people/square mile even in "“primitive settings"”). Population density for our purposes is most appropriately defined as people/square mile of arable land. Once a society begins to go down the road of increased population density, it'’s difficult to "“go back"” w/out mass die-off, so they tended to get caught in a cycle of food production-->higher density populations-->require particular patterns of food production.

High-density societies (i.e., farming societies) tend to have more people, a more complex system of organization, & greater trade specialization--—all of which offer certain advantages in contrast with societies which do not have these characteristics. In general, hunter-gatherer societies, when confronted with farming societies, have either 1) joined them, or 2) been replaced by them.

Correspondence between space for a society to expand and its methods of conflict resolution? One example Diamond cites is the Moriori tribe (of the Chatham islands) who were isolated and could not expand; they renounced war, and "“reduced potential conflicts from overpopulation by castrating some male infants."” Could the Caribbean islanders that Columbus massacred be another example of this correspondence?? [Later in the book Diamond cautions against the assumption that people w/in a society are not violent simply because one does not actually observe this violence taking place. Methods other than direct observation, such as gathering peoples'’ family histories, can reveal otherwise.] Population size certainly plays a role in conflict resolution w/in a given society, with a monopoly on the use of force becoming necessary as a society increases in size. In smaller societies, there are still enough kin-based bonds between members that there is plenty of impetus to nip conflicts in the bud. Additionally, communal, non-centralized decision-making becomes increasingly difficult in larger groups. Population densities in a given region also help determine how interaction and warfare between groups may play out. Whether a conquered group will simply relocate, or become annihilated, enslaved, or vassalized may depend upon the population density of the region in which the conflict takes place and the population density of the societies in question; e.g., a society must have a fairly complex system of organization in order to be able to make any sort of use of slaves on a large scale.

Germs: Epidemic diseases, not conquistadores, were the real shock troops of European colonization, advancing well ahead of the would-be conquerors and wiping out untold numbers (perhaps as high as 95%) of vulnerable natives. This fact is seen most readily in the colonization of the Americas, although epidemic disease also provided significant barriers to European colonization in tropical Asia, Africa, Indonesia, and New Guinea. Some major epidemics which have evolved from diseases of animals: smallpox, flu, tuberculosis, malaria, plague, measles, yellow fever, and cholera. Until WWII, more victims of war died of war-borne microbes than of battle wounds.

Characteristics of epidemic diseases: 1) pattern of infection; epidemics produce no cases for a long time, then a whole wave of cases, then no more cases again for awhile. 2) spread quickly through an entire population. 3) they are "“acute;"” w/in a short time hosts either die or recover completely; 4) those who recover tend to develop immunity from future infections of the same disease; 5) microbes causing epidemic diseases tend to be restricted to human hosts and do not move freely between other mediums; 6) require populations that are sufficiently numerous and dense in order to sustain themselves--—hence smaller populations cannot generally evolve epidemic diseases to pass on to others, because the disease cannot sustain itself. This latter characteristic also implies that epidemic diseases are relatively new to humankind, since we have only recently begun (since onset of agriculture) acquiring population sizes/densities adequate to maintain them.

Other ways in which farming contributes to the spread/evolution of epidemic disease: creating sedentary as opposed to nomadic societies, use of humanure for fertilizer, attraction of disease-carrying rodents to farmers'’ stored food, domestication of other social animals who have epidemic-disease causing germs of their own, and the development of vast trade routes amongst numerous sedentary societies, each w/ their own set of epidemic diseases.

Other kinds of diseases (i.e., non-epidemic types) can either maintain themselves in other mediums (e.g., soil or other animals), are chronic (i.e., they take a long time to kill their victim), or are nonfatal and thus survivors may not have immunity

Technology: e.g., weapons, writing/communication systems, political organization, transportation.

Each society has its own set of values and conditions which influence which technologies it accepts, and when, as well as its overall level of innovation and receptivity to innovation. These values of course differ between neighboring societies, and w/in a given society over time. Additionally, much if not most new technologies that a society encounters are not invented locally but are instead borrowed from other societies. Hence diffusion of technology between societies becomes very important, especially w/ increasing technological complexity. Proximity to competing societies may encourage a particular technology to be adopted; proximity also affects whether a particular technology, once adopted, is maintained. So again, Diamond comes back to a bio-geographical explanation for technological superiority in some societies as trumping any sort of a cultural explanation, because what mattered most ultimately was 1) time of onset of food production, 2) barriers to diffusion of technology and ideas, and 3) human population size. And again, Eurasia is at the advantage. Further, since technological development tends to catalyze greater technological development, early head-starts have a tendency to become exaggerated over time.

In the final section of his book, Diamond takes a brief (130 page) look at global history and applies the lessons learned thus far to explain the rise and fall of different societies, as well as examining the varying results of major population movements throughout history. His focus is on Australia/New Guinea/Polynesia, China/Southeast Asia, Africa, and the Americas, and he cites both archaeological and linguistic evidence to reinforce his analysis.

In the last chapter, Diamond sets the stage for his more recent book, "“Collapse"”: "Even from A.D. 1000-1450 the flow of science and technology was predominantly into Europe from the Islamic societies stretching from India to North Africa, rather than vice versa. During those same centuries China led the world in technology, having launched itself on food production nearly as early as the Fertile Crescent did."” So then why did the center of power in the ancient world shift continually westward, from the Fertile Crescent to Greece, then Rome, and finally to northern and western Europe? A major contributor appears to have been ecocide. "...Fertile Crescent and eastern Mediterranean societies had the misfortune to arise in an ecologically fragile environment. They committed ecological suicide by destroying their own resource base. Power shifted westward as each eastern Mediterranean society in turn undermined itself, beginning with the oldest societies, those in the east (the Fertile Crescent)...In effect, Europe received its crops, livestock, technology, and writing systems from the Fertile Crescent, which then gradually eliminated itself as a major center of power and innovation."”

With regards to China, Diamond largely faults political centralization, which enabled the Chinese empire to completely isolate itself through the decisions of a few individuals; compare this w/ politically dis-unified Europe, which consisted of numerous smaller nation-states locked in competition w/ one another. He gives numerous other examples to further illustrate this contrast between China and Europe, specifically around decisions to adopt or abandon particular technologies and/or technological processes.

The historical forces that Diamond cites are however just that--—historical. And while he is of course correct in his assertion that "...the hand of history'’s course at 8000 B.C. lies heavily on us..."”, in that it is unlikely that sub-Saharan Africans, Aboriginal Australians, and Native Americans will be dominating world affairs any time soon, it is also clear that powerful new forces have arisen in the modern world, forces which he cannot fully account for in Guns, Germs, and Steel. It begs the question, which environmental/geographical determinants are still relevant and most important in the modern world, and I am hoping that he poses somewhat of an answer to this question in his later work. He does at least entertain "...the broad range of questions concerning cultural idiosyncrasies [and the idiosyncrasies of individuals, hence acknowledging the "“Big Man"” historians], unrelated to environment and initially of little significance, that might evolve into influential and long-lasting cultural features..."” and acknowledges that "...their significance constitutes an important unanswered question."” Yet his initial thesis remains intact, as "“[this question]...can best be approached by concentrating attention on historical patterns that remain puzzling after the effects of major environmental factors have been taken into account."”

In addition to this set of questions--—perhaps the biggest, most important mysteries of human history left unaddressed by the book--—I also finished Guns, Germs, and Steel with more of an interest in the role that North Africa and the Indian subcontinent played in the development of ancient human civilization, as these areas were largely glossed over by Diamond.

The book also had a number of excellent charts and graphs which contributed significantly to the overall argument. In particular, I found the illustrations on pages 37, 87, 99, 135, 140, 162, 167, 177, 268-9, 362-3 quite useful, and have copies of them on-hand if anyone would like to see them as something of a supplement to my outline.