Guns, Germs, and Steel

My motive for investigating these geographic differences in human societies is not to celebrate one type of society over another but simply to understand what happened in history.

The settlement of Australia / New Guinea was perhaps associated with still another big first, besides humans’ first use of watercraft and first range extension since reaching Eurasia: the first mass extermination of large animal species by humans.

Hence it seems to me most likely that the giants were indeed exterminated by humans, both directly (by being killed for food) and indirectly (as the result of fires and habitat modification caused by humans).

The tragedy of the Moriori resembles many other such tragedies in both the modern and the ancient world, pitting numerous well-equipped people against few ill-equipped opponents.

Thus, Moriori and Maori societies developed from the same ancestral society, but along very different lines.

Atahuallpa was absolute monarch of the largest and most advanced state in the New World, while Pizarro represented the Holy Roman Emperor Charles V (also known as King Charles I of Spain),monarch of the most powerful state in Europe.

The Spaniards’ steel swords, lances, and daggers, strong sharp weapons that slaughtered thinly armored Indians. In contrast, Indian blunt clubs, while capable of battering and wounding Spaniards and their horses, rarely succeeded in killing them.

Throughout the Americas, diseases introduced with Europeans spread from tribe to tribe far in advance of the Europeans themselves, killing an estimated 95 percent of the pre- Columbian Native American population.

In short, plant and animal domestication meant much more food and hence much denser human populations. The resulting food surpluses, and (in some areas) the animal-based means of transporting those surpluses, were a prerequisite for the development of settled, politically centralized, socially stratified, economically complex, technologically innovative societies.

In short, only a few areas of the world developed food production independently, and they did so at widely differing times. From those nuclear areas, hunter-gatherers of some neighboring areas learned food production, and peoples of other neighboring areas were replaced by invading food producers from the nuclear areas.

What actually happened was not a discovery of food production, nor an invention, as we might first assume. There was often not even a conscious choice between food production and hunting-gathering. Instead, as we shall see, food production evolved as a by-product of decisions made without awareness of their consequences.

The shift from hunting-gathering to food production did not always coincide with a shift from nomadism to sedentary living.

Cereal crops have the virtues of being fast growing, high in carbohydrates, and yielding up to a ton of edible food per hectare cultivated. As a result, cereals today account for over half of all calories consumed by humans and include five of the modern world’s 12 leading crops (wheat, corn, rice, barley, and sorghum).

A mere dozen species account for over 80 percent of the modern world’s annual tonnage of all crops. Those dozen blockbusters are the cereals wheat, corn, rice, barley, and sorghum; the pulse soybean; the roots or tubers potato, manioc, and sweet potato; the sugar sources sugarcane and sugar beet; and the fruit banana.

Our failure to domesticate even a single major new food plant in modern times suggests that ancient peoples really may have explored virtually all useful wild plants and domesticated all the ones worth domesticating.

A second advantage of the Fertile Crescent flora is that the wild ancestors of many Fertile Crescent crops were already abundant and highly productive, occurring in large stands whose value must have been obvious to hunter- gatherers.

A third advantage of the Fertile Crescent flora is that it includes a high percentage of hermaphroditic “selfers”—that is, plants that usually pollinate themselves but that are occasionally cross-pollinated.

Thus, the hunter-gatherers of Tell Abu Hureyra were not wasting time and endangering themselves by collecting wild plants indiscriminately. Instead, they evidently knew the local wild plants as intimately as do modern New Guineans, and they used that knowledge to select and bring home only the most useful available seed plants.

Thus, the limits on indigenous food production in New Guinea had nothing to do with New Guinea peoples, and everything with the New Guinea biota and environment.

The ones that do adopt new crops, livestock, or technology may thereby be enabled to nourish themselves better and to outbreed, displace, conquer, or kill off societies resisting innovation.

This very unequal distribution of wild ancestral species among the continents became an important reason why Eurasians, rather than peoples of other continents, were the ones to end up with guns, germs, and steel.

In contrast, a domesticated animal is defined as an animal selectively bred in captivity and thereby modified from its wild ancestors, for use by humans who control the animal’s breeding and food supply.

Over a century ago, the British scientist Francis Galton summarized this discrepancy succinctly: 'It would appear that every wild animal has had its chance of being domesticated, that [a] few…were domesticated long ago, but that the large remainder, who failed sometimes in only one small particular, are destined to perpetual wildness.

All species for whose dates of domestication we have archaeological evidence were domesticated between about 8000 and 2500 B.C. —that is, within the first few thousand years of the sedentary farming-herding societies that arose after the end of the last Ice Age.

In all, of the world’s 148 big wild terrestrial herbivorous mammals—the candidates for domestication—only 14 passed the test. Why did the other 134 species fail? To which conditions was Francis Galton referring, when he spoke of those other species as 'destined to perpetual wildness'?

The evidence for predominantly single domestications in Southwest Asia, but frequent multiple domestications in the Americas, might thus provide more subtle evidence that crops spread more easily out of Southwest Asia than in the Americas.

The major killers of humanity throughout our recent history—smallpox, flu, tuberculosis, malaria, plague, measles, and cholera—are infectious diseases that evolved from diseases of animals, even though most of the microbes responsible for our own epidemic illnesses are paradoxically now almost confined to humans.

Around those axes turned the fortunes of history.

From a germ’s point of view, genital sores, diarrhea, and coughing are 'symptoms of disease.' From a germ’s point of view, they’re clever evolutionary strategies to broadcast the germ.

Knowledge brings power. Hence writing brings power to modern societies, by making it possible to transmit knowledge with far greater accuracy and in far greater quantity and detail, from more distant lands and more remote times.

The independent invention that we can trace in greatest detail is history’s oldest writing system, Sumerian cuneiform. For thousands of years before it jelled, people in some farming villages of the Fertile Crescent had been using clay tokens of various simple shapes for accounting purposes, such as recording numbers of sheep and amounts of grain.

Perhaps the most important single step in the whole history of writing was the Sumerians’ introduction of phonetic representation, initially by writing an abstract noun (which could not be readily drawn as a picture) by means of the sign for a depictable noun that had the same phonetic pronunciation.

Alphabets apparently arose only once in human history: among speakers of Semitic languages, in the area from modern Syria to the Sinai, during the second millennium B.C. All of the hundreds of historical and now existing alphabets were ultimately derived from that ancestral Semitic alphabet.

The kings and priests of ancient Sumer wanted writing to be used by professional scribes to record numbers of sheep owed in taxes, not by the masses to write poetry and hatch plots. As the anthropologist Claude Lévi-Strauss put it, ancient writing’s main function was 'to facilitate the enslavement of other human beings.

The history of writing illustrates strikingly the similar ways in which geography and ecology influenced the spread of human inventions.

In fact, many or most inventions were developed by people driven by curiosity or by a love of tinkering, in the absence of any initial demand for the product they had in mind.

Inventors often have to persist at their tinkering for a long time in the absence of public demand, because early models perform too poorly to be useful.

The key question about the laundry list is whether such factors differed systematically from continent to continent and thereby led to continental differences in technological development.

Just like industrialized Europe and America, traditional New Guinea has conservative societies that resist new ways, living side by side with innovative societies that selectively adopt new ways.

Because technology begets more technology, the importance of an invention’s diffusion potentially exceeds the importance of the original invention.

The second jump resulted from our adoption of a sedentary lifestyle, which happened at different times in different parts of the world, as early as 13,000 years ago in some areas and not even today in others.

Despite these very early first steps, neither pottery nor weaving took off until people became sedentary and thereby escaped the problem of transporting pots and looms.

Hence, all other things being equal, technology develops fastest in large productive regions with large human populations, many potential inventors, and many competing societies.

For any ranked society, whether a chiefdom or a state, one thus has to ask: why do the commoners tolerate the transfer of the fruits of their hard labor to kleptocrats?

The most distinctive economic feature of chiefdoms was their shift from reliance solely on the reciprocal exchanges characteristic of bands and tribes, by which A gives B a gift while expecting that B at some unspecified future time will give a gift of comparable value to A.

Every state has its slogan urging its citizens to be prepared to die if necessary for the state: Britain’s “For King and Country,” Spain’s “Por Dios y España,” and so on. Such sentiments are unthinkable in bands and tribes.

The size of the regional population is the strongest single predictor of societal complexity. As we have seen, bands number a few dozen individuals, tribes a few hundred, chiefdoms a few thousand to a few tens of thousands, and states generally over about 50,000.

Considerations of conflict resolution, decision making, economics, and space thus converge in requiring large societies to be centralized. But centralization of power inevitably opens the door—for those who hold the power, are privy to information, make the decisions, and redistribute the goods—to exploit the resulting opportunities to reward themselves and their relatives.

Among all those chiefdoms, the ubiquitous problem of devising centralized power structures was solved most successfully by a chief called Dingiswayo, who gained ascendancy of the Mtetwa chiefdom by killing a rival around 1807.

The Aztec and Inca Empires were formed by 15th-century conquests, before Europeans arrived, but we know much about their formation from Indian oral histories transcribed by early Spanish settlers.

New Guinea thus joins the Fertile Crescent, China, and a few other regions as one of the world’s centers of independent origins of plant domestication.

New Guinea’s population is not only small in aggregate, but also fragmented into thousands of micropopulations by the rugged terrain.

The Aboriginal Australian substitute for food production has been termed “firestick farming.” The Aborigines modified and managed the surrounding landscape in ways that increased its production of edible plants and animals, without resorting to cultivation.

The most extreme losses of technology in the Australian region took place on the island of Tasmania, 130 miles off the coast of southeastern Australia.

The documented instances of technological regression on the Australian mainland, and the example of Tasmania, suggest that the limited repertoire of Native Australians compared with that of peoples of other continents may stem in part from the effects of isolation and population size on the development and maintenance of technology.

The people who did create a society in Australia were Aboriginal Australians. Of course, the society that they created was not a literate, food- producing, industrial democracy. The reasons follow straightforwardly from features of the Australian environment.

China’s size and ecological diversity spawned many separate local cultures, distinguishable archaeologically by their differing styles of pottery and artifacts. In the fourth millennium B.C. those local cultures expanded geographically and began to interact, compete with each other, and coalesce.

All these geographic factors contributed to the early cultural and political unification of China, whereas western Europe, with a similar area but a more rugged terrain and no such unifying rivers, has resisted cultural and political unification to this day.

So overwhelming was this Chinese steamroller that the former peoples of tropical Southeast Asia have left behind few traces in the region’s modern populations.

The population movement that brought Achmad’s and Sauakari’s ancestors to Java and New Guinea, respectively, termed the Austronesian expansion, was among the biggest population movements of the last 6,000 years.

Austronesian languages are spoken today as native languages over more than half of the globe’s span, from Madagascar to Easter Island.

The linguistic evidence suggests that many tropical crops were added to the Austronesian repertoire after the emigration from Taiwan.

Depending on their geographic homeland, East Asian and Pacific peoples differed in their access to domesticable wild plant and animal species and in their connectedness to other peoples. Again and again, people with access to the prerequisites for food production, and with a location favoring diffusion of technology from elsewhere, replaced peoples lacking these advantages.

The most glaring difference between American and Eurasian food production involved big domestic mammal species. In contrast, the Americas had only one species of big domestic mammal, the llama / alpaca, confined to a small area of the Andes and the adjacent Peruvian coast.

These examples demonstrate that the sole missing ingredients required to sustain food production in large areas of the Americas were domestic animals and crops themselves.

The infectious diseases that regularly visited crowded Eurasian societies, and to which many Eurasians consequently developed immune or genetic resistance, included all of history’s most lethal killers: smallpox, measles, influenza, plague, tuberculosis, typhus, cholera, malaria, and others.

Eurasian societies enjoyed a huge advantage in their sources of power to operate machines. The earliest advance over human muscle power was the use of animals—cattle, horses, and donkeys—to pull plows and to turn wheels for grinding grain, raising water, and irrigating or draining fields.

Eurasia’s long head start on human settlement; its more effective food production, resulting from greater availability of domesticable wild plants and especially of animals; and its less formidable geographic and ecological barriers to intracontinental diffusion.

The populations of Iceland and Norway themselves were too small and too poor for them to continue their support of the Greenland Norse population.

The end result has been the elimination of populous Native American societies from most temperate areas suitable for European food production and physiology.

Most Americans and many Europeans equate native Africans with blacks, white Africans with recent intruders, and African racial history with the story of European colonialism and slave trading.

Africa’s diverse peoples resulted from its diverse geography and its long prehistory. Africa is the only continent to extend from the northern to the southern temperate zone, while also encompassing some of the world’s driest deserts, largest tropical rain forests, and highest equatorial mountains.

Sorghum proved so valuable that it is now grown in areas with hot, dry climates on all the continents, including in the United States.

With the addition of iron tools to their wet-climate crops, the Bantu had finally put together a military-industrial package that was unstoppable in the subequatorial Africa of the time.

All human societies contain inventive people. It’s just that some environments provide more starting materials, and more favorable conditions for utilizing inventions, than do other environments.

Thus, 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.

In contrast, Europe’s geographic balkanization resulted in dozens or hundreds of independent, competing statelets and centers of innovation. If one state did not pursue some particular innovation, another did, forcing neighboring states to do likewise or else be conquered or left economically behind.

These examples illustrate the broad range of questions concerning cultural idiosyncrasies, unrelated to environment and initially of little significance, that might evolve into influential and long-lasting cultural features.

Historical sciences in the broad sense (including astronomy and the like) share many features that set them apart from nonhistorical sciences such as physics, chemistry, and molecular biology. I would single out four: methodology, causation, prediction, and complexity.

In historical sciences, one can provide a posteriori explanations (e.g., why an asteroid impact on Earth 66 million years ago may have driven dinosaurs but not many other species to extinction), but a priori predictions are more difficult.

6. The development of human societies on different continents is discussed, focusing on the factors that influenced their evolution.

Around 13,000 years ago, as glaciers melted rapidly all over the world, conditions in Japan changed spectacularly for the better, as far as humans were concerned.

The end of the Ice Age was accompanied by the first of the two most decisive changes in Japanese history: the invention of pottery.

Jomon people lived at some of the highest population densities ever estimated for hunter-gatherers, especially in central and northern Japan with its nut-rich forests, salmon runs, and productive seas.

Jomon Japan was a conservative miniature universe that maintained its isolation and changed surprisingly little over the course of 10,000 years— an island of stability in a fragile, rapidly changing contemporary world.

The other decisive change, which triggered a second population explosion, began around 400 B.C. with the arrival of a new lifestyle (and people?) from South Korea.

Reluctant as Japanese and Koreans are to admit it, they are like twin brothers who shared their formative years. The political future of East Asia depends in large part on their success in rediscovering those ancient bonds between them.

My main conclusion was that societies developed differently on different continents because of differences in continental environments, not in human biology.

What is the best way to organize human groups, organizations, and businesses so as to maximize productivity, creativity, innovation, and wealth? Should your group have a centralized direction (in the extreme, a dictator), or should there be diffuse leadership or even anarchy?

The German beer industry suffers from small-scale production. There are a thousand tiny beer companies in Germany, shielded from competition with one another because each German brewery has virtually a local monopoly, and they are also shielded from competition with imports.

The efficiency of the Japanese food-processing industry is a miserable 32 percent that of ours. There are 67,000 food-processing companies in Japan, compared to only 21,000 in the United States, which has twice Japan’s population—so the average U.S. food-processing company is six times bigger than its Japanese counterpart.

If your goal is innovation and competitive ability, you don’t want either excessive unity or excessive fragmentation. Instead, you want your country, industry, industrial belt, or company to be broken up into groups that compete with one another while maintaining relatively free communication.

David Steadman summarizes recent evidence that extinction waves accompanied human settlement of Pacific islands in his paper “Prehistoric extinctions of Pacific island birds: Biodiversity meets zooarchaeology,” Science 267:1123–31 (1995).

Three classic accounts of disease in history are Hans Zinsser, Rats, Lice, and History (Boston: Little, Brown, 1935), Geddes Smith, A Plague on Us (New York: Commonwealth Fund, 1941), and William McNeill, Plagues and Peoples (Garden City, N.Y.: Doubleday, 1976).

The reverse phenomenon, of European deaths due to diseases encountered overseas, is discussed by Philip Curtin, Death by Migration: Europe’s Encounter with the Tropical World in the 19th Century.

The fourfold classification of human societies into bands, tribes, chiefdoms, and states owes much to two books by Elman Service: Primitive Social Organization (New York: Random House, 1962) and Origins of the State and Civilization (New York: Norton, 1975).

10. The book concludes by applying these insights to different continents, highlighting the unique trajectories of each region.

9. The book discusses the evolution of human societies from bands to tribes, chiefdoms, and states.

8. The evolution of food production and its impact on human civilization is explored.

7. The book discusses the impact of plant and animal domestication on human societies."

4. The colonization of Australia and New Guinea is discussed, emphasizing its significance as the earliest known instance of humans using watercraft.

3. The role of diseases, writing, and technology in societal development is explored.

2. It discusses the transition from hunting-gathering to agriculture and the impact of geography on the spread of food production.

1. The book rejects the notion of racial or cultural superiority, attributing societal advancement to environmental factors and access to resources.

In short, literacy made the Spaniards heirs to a huge body of knowledge about human behavior and history. By contrast, not only did Atahuallpa have no conception of the Spaniards themselves, and no personal experience of any other invaders from overseas, but he also had not even heard (or read) of similar threats to anyone else, anywhere else, anytime previously in history.

The adoption of food production exemplifies what is termed an autocatalytic process—one that catalyzes itself in a positive feedback cycle, going faster and faster once it has started.

The winners of past wars were not always the armies with the best generals and weapons, but were often merely those bearing the nastiest germs to transmit to their enemies.

Eurasia’s considerable initial advantage thereby was translated into a huge lead as of A.D. 1492—for reasons of Eurasia’s distinctive geography rather than of distinctive human intellect.

The big-man has no independent decision-making authority, knows no diplomatic secrets, and can do no more than attempt to sway communal decisions. Big-men achieve that status by their own attributes; the position is not inherited.

The variable outcomes of the Austronesian expansion strikingly illustrate the role of food production in human population movements. Austronesian food-producers migrated into two regions (New Guinea and Indonesia) occupied by resident peoples who were probably related to each other.

The search for answers is difficult because the evidence is so conflicting. On the one hand, the Japanese people are biologically undistinctive, being very similar in their appearance and genes to other East Asians, especially to Koreans.

The Musket/Potato Wars illustrate the main process running through the history of the last 10,000 years: human groups with guns, germs, and steel, or with earlier technological and military advantages, spreading at the expense of other groups, until either the latter groups became replaced or everyone came to share the new advantages.

5. The encounter between the Inca emperor Atahuallpa and the Spanish conquistador Francisco Pizarro is presented as a significant event in world history.