Guns, Germs, And Steel Book Summary, by Jared Diamond Ph.D.

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1-Page Summary of Guns, Germs, And Steel

The prologue begins with the author’s conversation with Yali, a New Guinean politician. The two were talking about how different their cultures were and why that was. It turns out that neither of them considered any genetic differences between Europeans and New Guineans to be responsible for these cultural differences. Yali asked, “Why is it that you white people developed so much cargo (inventions) and brought it to New Guinea, but we black people had little cargo of our own?”

Diamond realized that the same question applied to other groups. For example, Eurasian groups have dominated in wealth and power. Other peoples are still struggling after throwing off colonial domination. Still others were decimated by European colonization efforts.

Many indigenous peoples have been conquered by societies that had advanced technology and immunology, such as Native Americans, Aboriginal Australians, and South Africa’s Khoisan tribes. This is due to the fact that these more technologically-advanced societies were able to conquer their less-advanced neighbors.


The title of the book refers to the three factors that enabled European nations to conquer and dominate other societies: guns, germs, and steel.

Diamond argues that certain environmental characteristics, such as geography and weather, led to the development of stable agricultural societies. These characteristics also allowed for the growth of powerful states due to their immunity to disease.

Outline of theory

Diamond argues that Eurasian civilization is not so much a product of ingenuity, but of opportunity and necessity. That is, civilization was created out of the right conditions for success rather than superior intelligence.

The first step towards civilization is the move from nomadic hunter-gatherers to agrarian societies. Several conditions are necessary for this transition: access to carbohydrates that are easy to store; dry climates that allow for storage; and animals that can be domesticated and survive captivity. Control of these elements leads to food surpluses, which free people up so they can specialize in other areas besides sustenance. The combination of specialization and population growth leads to social innovations like bureaucracy, government, and eventually empires.

Although agriculture arose in several parts of the world, Eurasia gained an early advantage over other areas because it had more species that were suitable for domestication. In particular, Eurasia has barley and wheat as well as three types of pulses (beans) which are rich in protein. These grains were easier to sow and store than American maize or tropical bananas.

As early as the Bronze Age, people began to trade with other civilizations in adjacent territories. This led to them discovering more useful animals such as horses and donkeys for use in transportation. Diamond argues that there are 13 species of large domesticated animals over 100 pounds (45kg) compared to one in South America (counting llamas and alpacas together), none in the rest of the world, Australia or North America suffered from a lack of useful animals due to extinction shortly after The Pleistocene Era whereas New Guinea only had a few during their settlement by Asian Austronesians some 4,0005,000 years ago. Many biological relatives of horses such as zebras and onagers were untameable; African elephants could be tamed but breeding was difficult so only 14 out of 148 “candidates” could be successfully domesticated including all large mammals that have been able to be tamed.

Eurasians domesticated animals such as goats, sheep, cows, and horses for clothing. They also used them to till the fields and transport goods.

The Eurasian landmass is larger than the American one, which gave it more advantages. The large area allowed for more plant and animal species to be domesticated, and the east-west orientation of Eurasia made those breeds available in other parts of the continent through similarities in climate and seasonal changes. North America had trouble adapting crops that were originally domesticated at one latitude because they couldn’t survive at different latitudes (and vice versa). Africa was also fragmented by its extreme variations in climate from north to south; plants or animals that thrived in one part never reached others where they could have flourished because they could not survive between areas. Europe took advantage of this situation by adopting Southwestern Asia’s animals, plants, and agricultural techniques first, then spreading them throughout Europe.

The abundant supply of food and the dense populations that it supported made division of labor possible. The rise of non-farming specialists such as craftsmen and scribes accelerated economic growth and technological progress, which eventually led to Europe’s domination over other continents with the use of guns and steel in recent centuries.

It is believed that Eurasia has a large population, high levels of trade and living in close proximity to livestock. This resulted in widespread transmission of diseases between animals and humans. Smallpox, measles and influenza were the result of close proximity between dense populations of animals and humans. Natural selection forced Eurasians to develop immunity to a wide range of pathogens (diseases). When Europeans made contact with the Americas, European diseases (to which Americans had no immunity) ravaged the indigenous American population rather than vice versa. The germs decimated indigenous populations so that relatively small numbers of Europeans could maintain their dominance over North America.

Diamond claims that Europe’s geography helped it colonize the world. This is because western Europe has many small countries, which are closer to each other than large empires like China. Western European nations were forced to compete with each other and not get lazy or else they would be outdone by their neighbors. In addition, western European countries had a temperate climate while southwestern Asia did not; therefore, Europeans could grow food better than Asians.


The book Guns, Germs, and Steel talks about why some civilizations were more successful than others. It says that it was because of agriculture. People who could farm had access to food and other resources which allowed them to specialize in things like mining and literacy.

The development of agriculture is dependent on the availability of plants that are easy to domesticate. In the Fertile Crescent, there were many wild plant species suitable for domestication. However, in America, farmers had to struggle with developing corn from its wild ancestor because it was not very useful or nutritious.

Also important to the change from hunter-gatherers to agrarian societies was having large domesticable animals. There were only 14 of them, and five of these were native to Eurasia. The llama and alpaca are both South American species, but they’re the only ones that live outside temperate Eurasia.

Due to the Anna Karenina principle, only a few animals are suitable for domestication. These include animals that are docile, gregarious and willing to breed in captivity. Also, the animal must have a social dominance hierarchy which allows humans to easily control them. Since Africa has many large mammals that do not fall into this category (e.g., zebras), it is unlikely that they were ever domesticated by humans (although some can be tamed). The Holocene extinction event eliminated many of the megafauna from continents such as Australia and America where people had no prior experience with these kinds of animals before their arrival on those continents.

Smaller domestic animals, such as dogs and cats, are helpful to an agricultural society but won’t sustain a large-scale agrarian society. Larger animals like cattle and horses have important roles in plowing the land, allowing for greater crop productivity and the ability to farm a wider variety of soil types than would be possible without them. They also help with transportation of goods and people over long distances, giving societies that possess them military advantages.


Diamond also argues that geography made it difficult for humans to migrate. This is because of the climate and latitude, as well as how far animals can travel in a certain area.

The dominant theory is that modern humans developed in Africa. The Sahara desert prevented people from migrating north to the Fertile Crescent, until later when the Nile River valley became accommodating.

Diamond explains how the development of technology affected hunter-gatherers. He talks about their rapid adoption of new technologies and its effects on them.

In the book Guns, Germs, and Steel, Jared Diamond talks about why Europe became so powerful compared to East Asia. He says that the geographical features of West Europe allowed for competition between nations which forced innovation in technology. The geography of Eastern Asia was not as conducive to competition between nations and led to stagnation in technology.


During colonization of the Americas, 95% of indigenous populations were killed off. They died from diseases brought by Europeans such as smallpox and measles. Similar circumstances were observed in Australia and South Africa, where Aboriginal Australians and Khoikhoi populations were decimated by smallpox, measles, influenza and other diseases.

How did Europeans survive when they encountered diseases in the Americas? Diamond believes that most epidemic diseases only occur in densely populated areas, and that European societies had been exposed to more disease because of the combination of farming and domesticated animals.

The author mentions that tropical diseases limited European penetration into Africa. He notes that there were a few exceptions, such as malaria in Africa.

Success and failure

Guns, Germs and Steel focuses on why some populations are more successful than others. In his later book, Collapse: How Societies Choose to Fail or Succeed, he examines environmental factors and other reasons that have led to the decline of certain societies.

Full Summary of Guns, Germs, And Steel

Overall Summary

In Guns, Germs, and Steel, Jared Diamond examines the idea that differences between societies are due to geographical reasons. The book is framed as a response to Yali’s question about why European society has been so successful compared with other societies.

The book begins by discussing the differences between civilizations. It also talks about how civilization started and why there are so many differences in them today. For example, let’s take a look at the Inca Empire and Spain during the 15th century. The Spanish were able to conquer the Incas because they had guns while the Incas didn’t have any weapons at all for protection.

In Part Two, Diamond talks about how agriculture started and why it arose in certain parts of the world but not others. Using carbon-dating technology, archaeologists have determined that the first sites of agriculture were Mesopotamia (in the Middle East), followed by Mesoamerica and China. Agriculture arose in those areas for a few reasons. Most people at the time lived as hunter-gatherers, meaning they hunted game and picked nuts and berries for food. But in the parts of the world that first developed agriculture, game was becoming scarcer due to overhunting or because climate change made fruit less plentiful; therefore these early peoples had to experiment with new forms of food production. In Mesopotamia, ancient humans used trial and error to learn how to plant certain large seeds in the earth resulting in crops that could be harvested and converted into highly nutritious foods like corn (maize). These early peoples also learned how to domesticate wild animals such as dogs, cows, buffalo etc., breeding familiar modern animals from them; they used their domesticated animals to assist with agricultural work while also learning how to domesticate certain wild crops like wheat (from which we get bread) through selective breeding—breeding plants together until desirable traits are passed on from one generation of plants onto another generation—producing most of our familiar modern crops today such as rice (“Oryza”) barley (“Hordeum”), peas (“Pisum”), flax (“Linum usitatissimum”), sorghum (“Sorghum bicolor”, “Sorghum vulgare”) etc.).

Agriculture arose in Mesoamerica and China. However, due to environmental factors like soil fertility and the availability of domesticable animals, agriculture took longer to be adopted by people living in other areas. Once it had arisen around the world, however, agricultural innovations spread from east to west much faster than they spread north to south—this is because the Earth spins on an east-west axis, meaning that areas with similar latitudes have a similar climate and environment. Archaeological data indicates that these innovations diffused from east to west sooner than they diffused north or south.

In Part Three, Diamond explains how differences between early agricultural societies grew over time. Agricultural societies had domesticated animals and were constantly in close proximity to them. As a result of this, they were exposed to germs that caused diseases like smallpox more often than hunter-gatherer societies were; those who didn’t have immunity died off while the ones who did lived on and passed their immunities down to their offspring.

Another important development in the history of agricultural societies was the invention of written language. While it’s hard to say exactly why writing emerged, we know that agriculture society requires a lot of record keeping and crops require lots of attention. Therefore, people needed a way to communicate with one another. Furthermore, east-west diffusion ensured that once one society developed language, it diffused into surrounding areas because they were similar in latitude and climate.

The history of language has a lot in common with the development of technology. It’s hard to explain why certain inventors develop certain technologies, but people were more likely to experiment with resources and materials in agricultural societies than hunter-gatherer societies because those agricultural societies had more leisure time and they were denser, which means that ideas spread faster. As a result, there are many new technologies from agricultural societies that have been passed on to neighboring ones.

Civilizations throughout history have tended to develop into large, complex societies. Early civilizations were small and simple but eventually grew in size as they formed either through conquest or by joining together. As these civilizations grew larger, so did their centralized power structures—that is, the leaders who commanded a group of subordinates who then ruled over local people. States used a balance of kleptocracy (the rulers ordering their subjects to give up some possessions) and religion or patriotism to maintain control. The state became the dominant mode of society around 1600 when Europe began its colonization of America.

In Part Four, Diamond looks at a series of case studies that support his theory. In the first, he demonstrates that the New Guineans developed agriculture, sophisticated technology, and political centralization while their neighbors in Australia did not do so because they were geographically isolated from each other. He also argues that China was able to become the world’s first large state because it had temperate weather and similar geography between states which made communication easier. The New Guineans were more successful than their neighbors in Java and Borneo in staving off European colonization through malaria resistance from agricultural practices. In the New World, agriculture arose in certain regions but didn’t diffuse to neighboring regions due to geographic barriers like deserts or mountains. Finally, Diamond argues that African peoples who lived north of sub-Saharan Africa were more militarily successful than those below due to some limited forms of agriculture allowing time for complex technologies (like weapons) development whereas people living south couldn’t develop any form of agriculture so they never had time or organization for developing complex technologies.

In conclusion, Diamond argues that the differences between different peoples and societies are largely attributable to geographic differences. In certain parts of the world, humans began pursuing agriculture because the fertile soil and temperate climate made it a good use of time and resources. As agricultural societies gained technological advantages over non-agricultural ones, they were able to conquer them.


The author of the book, Jared Diamond, has spent most of his life studying why different human civilizations developed in different ways.

Diamond once met a politician from New Guinea named Yali. He was interested in the history of colonialism and wanted to know how it had affected his country.

The author describes the differences between New Guineans and white colonists who came to New Guinea in the 1800s. Although Europeans were racist towards them, they’re still intelligent people. Yali’s question for Diamond is: “Why did you white people develop so much cargo (technology) while we black people had little cargo of our own?” This book attempts to answer that question by analyzing evolution and human history.

Yali’s question is about the differences between different civilizations. Some have used their power and wealth to dominate other people, such as those in Europe and Eastern Asia. Diamond asks why this happened, since it didn’t happen the other way around. In general, he wants to know why human development proceeded at different rates on different continents?

In this passage, Jared Diamond is responding to possible objections to his book. One of those objections could be that he’s glorifying the Europeans for their conquests. However, he says that’s not true at all and clarifies what his book is about. He also explains why it’s important to study different cultures around the world.

One could also interpret Diamond to be saying that hunter-gatherers are inferior to agricultural or industrial civilizations. He doesn’t say they’re not, but he does argue that they have fewer advantages than we do.

People have tried to answer this question for centuries, with some believing that Europeans were naturally superior. However, Darwin’s theory of evolution in the 1800s showed that there was no evidence to support such a claim. In fact, it is just plain wrong and racist because hunter-gatherers are not less intelligent or talented than those living in industrialized countries.

In the book Guns, Germs and Steel, Jared Diamond talks about his experiences as an anthropologist in New Guinea. In New Guinea, he met a lot of smart people who were capable of doing things that Westerners couldn’t do. For example, they could track animals better than Westerners could because they had more experience tracking them. Furthermore, these people spent less time watching TV than average Westerners did; instead they spent more time exploring their surroundings.

Another explanation for human inequality across cultures was that people living in colder climates had to work harder and be more industrious. This isn’t true either, since Europeans who lived in cold places actually got their ideas from warmer areas.

Another answer to Yali’s question is that civilizations near rivers are more successful. This was true of ancient Egypt and Mesopotamia, both of which developed near big rivers. However, it turns out that these civilizations didn’t develop their irrigation systems until after they had already developed complex bureaucracies, the basis for government and society.

Diamond claims that guns, germs and steel are the main reasons why some civilizations were more successful than others. However, there are many other factors involved in determining a civilization’s success. For example, there are many societies with access to metal that never developed serious metallurgy.

Many scientists have studied why civilizations succeed. Some of them focus on the environment, others on technology and so forth. What Jared Diamond will do is give an overarching explanation for these specialists’ findings: he will answer Yali’s question in a big way. He’ll say that history followed different courses because of differences among people’s environments, not biological differences between the people themselves.

Diamond’s book is about the history of human evolution and how it led to Western domination. It also looks at bacteria and microbes, as well as writing. In addition, he examines case studies in various parts of the world.

Chapter 1

To begin, Diamond will talk about how human evolution has shaped the world we live in today. Humans are closely related to apes and primates. The earliest species of humans emerged about seven million years ago in Africa. Around one million years ago, Homo erectus began to migrate around the world—to Europe, Australia, Asia, etc.—where they evolved into modern humans (Homo sapiens). Scientists agree that modern humans first appeared half a million years ago and were distinguished from their ancestors by their larger skulls and ability to make fire.

Humans have left many traces of their existence on Earth. We can see that they began to use tools such as needles, awls, etc., and created large houses and buildings. Scientists are unsure where the Great Leap first appeared but it was crucial in human history.

After the “Great Leap Forward”, humans developed watercraft and began to travel around the world. They went to New Guinea, where they killed off many animals soon after arriving. Other scientists argue that this was not due to human activity, but rather because of an unrelated environmental change like a drought.

Humans have been living in Eurasia and Australia for 40,000 years. However, the Americas were not colonized until 35,000 to 14,000 years ago. The first people who came through America may have traveled across the Bering land bridge from Asia into Patagonia (in South America). This happened during a time when many large animals became extinct due to hunting by humans in other parts of the world. Evidence of this has been found in western United States as well as farther south; however there is also evidence that earlier settlements existed before these ones.

Humans spread to many parts of the world after they left Africa. Although there were humans in different places, some areas weren’t settled by them until recently; for example, Iceland was uninhabited until the 9th century. This leads to a question: why wasn’t Africa more powerful than other regions? The answer is that it had an early start on human life and therefore has 5 million years of proto-human existence compared with other continents.

Diamond tries to explain why Africa is the only continent that has not developed a civilization. A few thousand years ago, it seemed like any other continent would develop into the dominant one. However, looking back on history, we can see that Africa had more protohumans (evolutionary ancestors to Homo sapiens) than any other country and more genetic diversity as well. 11,000 years ago people in Australia had already built boats and were technologically advanced compared to what was happening in Africa at the time. In Eurasia there was more geographic diversity than anywhere else on Earth suggesting that people who lived in Eurasia would adapt to many different environments and therefore colonize many different parts of the world.

In a nutshell, Diamond says that any region of the world where humans existed 11,000 years ago was going to become dominant. He claims that Eurasia became the most powerful because it had many advantages over other regions.

Chapter 2

In 1835, the Chatham Islands were invaded by a Maori tribe. The Moriori people had been living there for thousands of years and were attacked, murdered, and driven out by the invading Maori tribe. Their cultures differed greatly because one was based on farming while the other was hunter-gatherer. Jared Diamond will try to understand why they pursued different paths of development.

There are thousands of islands in the Pacific, each with a different climate and elevation. There is an incredible amount of diversity among flora and fauna on these islands because they reflect the environmental differences between them. However, Polynesians colonized all those islands at approximately the same time by using boats to travel from island to island. This means that environmental factors led societies to branch off in different directions.

The Moriori people chose a hunter-gatherer culture because their island could not support crops. Also, the Chatham Islands were too small to allow for agriculture. The Moriori agreed to stop fighting and cooperate with one another. There was no strong government structure on the islands, nor any weapons of war. In contrast, there were about 100,000 Maori in Polynesia who fought over land and resources when they met the Moriori people during colonization by Europeans. As a result of this conflict, the Maori slaughtered most of them within days.

The Polynesians came to the islands thousands of years ago, but they all adapted to their surroundings. Diamond breaks up the environment into categories: climate, geological activity, flora and fauna (i.e., marina), area, terrain fragmentation, and isolation (proximity). For each category there are differences between islands which cause societal differences. For example, moist warm climates favor agriculture because crops grow easily. Volcanic activity in Polynesia produces hard shiny stones that can be used for tools. Certain Polynesian islands have rocky coasts meaning people who lived there could not obtain fish from those areas (marina).

Environmental differences between Polynesian islands partly explain differences in subsistence. The nomads who came to Polynesia brought pigs, dogs, and chickens with them to their islands. Meanwhile, the people of Easter Island only brought chickens because they didn’t have access to coral reefs or shallow waters for fishing. Because they couldn’t fish, they raised poultry instead. Other islanders from Tonga and Anuta adapted by developing agricultural techniques for taro cultivation because of warmer environments.

One way to classify Polynesian civilizations is by population density. The Chatham Islands, which were hunter-gatherers, had 5 people per square mile, while the Anuta Island agriculturalists had 1,100 people per square mile. Densely populated societies tend to have much more diverse societies with many different professions and political organizations. Hawaii is a textbook example of a dense society: before Europeans colonized it in the late 1700s, Hawaiians had extensive agriculture and eight distinct levels of society.

Polynesian societies became more complex as they had a denser population and access to more resources. In the Chatham Islands, where there was a small population and few resources, decisions were made by simple group consensus. However, in Hawaii or Tonga, there were hereditary chiefs who decided how land and food would be divided up.

The Polynesians made different kinds of artifacts based on the resources available. On the Chathams, houses were small and simple because there was little volcanic rock or metal. In Tonga or Marquesas where more natural resources were available, there were larger buildings and more complex tools.

Diamond argues that Polynesia is a good example of how huge societal differences arise from environmental differences. He concludes that we can generalize our findings to the rest of the world, but he also wonders if his conclusions are valid for other regions in the world.

Chapter 3

The biggest population shift in modern times was the movement of Europeans to the New World. It started with small expeditions and grew into more elaborate ones by the early 1500s. One example is when Francisco Pizarro, a Spanish explorer, met Atahuallpa, who was king of the Incas in present-day Peru. The Spaniards were outnumbered but managed to kidnap Atahuallpa despite being on his home turf.

Pizarro traveled through the Inca empire, using torture to extract information from captured people. This led him and his men to Atahuallpa’s palace in the center of the kingdom. When he met Pizarro, Atahuallpa willingly walked into his camp without protection. However, when Pizarro tried to open a copy of the Bible at their meeting, Atahaullpa refused it. He was then captured by soldiers outside and killed many more Incas before taking over their entire kingdom.

The author goes back to discuss the history of weapons. Some historians have argued that Spanish conquistadors were seen as intimidating or even gods, but they actually won because they had better weapons than Native Americans. Horses also gave them an advantage over their opponents who didn’t have horses themselves.

Guns were not the biggest advantage in Pizarro’s victory. He only had about a dozen of them, and they were difficult to load. His biggest advantage was steel: his soldiers’ swords and lances that killed Incas, as well as their armor that protected them from clubs. Horses also played an important role in helping him defeat the Incas.

The Incan empire was based out of an area that Francisco Pizarro would later name Cajamarca. The emperor moved to the area because of a smallpox epidemic in another part of the empire. Historians now know that earlier European explorers caused this epidemic. Overall, Europeans were killed by diseases brought from America more than they were killed by American-borne diseases.

Why did Pizarro come to the Americas? Diamond asks. Why didn’t Atahuallpa sail to Europe? Pizarro’s voyage was made possible by European maritime technology as well as complex political organizations that financed his travels. The Incas lacked all three essential precursors for maritime exploration (writing, centralization, and naval technology), or only had them in simplified versions.

Why did Atahuallpa fall for Pizarro’s trap? He didn’t bring soldiers because he didn’t know much about the Spanish. The Incas had a writing system, but it was simple and not used frequently. More importantly, Atahuallpa couldn’t read or write so he lacked knowledge of human behavior and history. Therefore, he hadn’t heard of devious invaders before.

Pizarro conquered the Inca Empire because of his superior technology, including horses and guns. He also had Europe’s diseases that killed many Native Americans. In addition, he was able to communicate with other European leaders using writing, which helped him plan for future conquests. However, we still haven’t addressed the question of why Europeans were so much more successful than Native Americans in the first place. Diamond will address this question later in his book by analyzing other factors such as geography and climate.

Chapter 4

Diamond worked on a farm in Montana when he was young. He witnessed a white farmer and Levi, an Indian man, argue about the ship that brought the farmer from Switzerland to America.

This chapter focuses on food production and the role it plays in civilization. Food is a necessity for life, and agriculture is one of the most efficient ways to produce food. It was first discovered about 11,000 years ago, which led to other innovations like guns, germs and steel that we’ll cover later on.

Agriculture is an efficient way to produce food because it can feed more people than hunting and gathering. It does this by keeping animals in a small area so humans don’t have to chase after them, and by growing crops in a small area instead of looking for berries across a wide area.

Agriculture is also important because it leads to social specialization. In a hunter-gatherer society, there are no job specializations beyond hunting and gathering. However, in an agricultural society, food needs to be stored for long periods of time (e.g., harvested crops need to be kept safe from animals). This leads to social specialization in two main ways: political leaders gain control over the food supply, and people have more leisure time so they can experiment with resources and develop new jobs that aren’t related directly to agriculture.

Agricultural societies are better at sustaining wars than hunter-gatherer societies because they have a tax base that allows them to support an army. In addition, agricultural societies learn how to domesticate animals and use those domesticated animals in warfare.

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Chapter 5

It’s a mystery why humans didn’t learn to produce food in areas of the globe that are, theoretically, good for growing crops. People from California, Argentina and Australia never developed agriculture even though later people did grow crops there.

Archaeologists can find out about ancient civilizations by carbon dating the ruins of those places and determining their ages. The remains of plants and animals from the same period will be in the area, often as charcoal from a fire. It’s sometimes difficult to tell if certain plants or animals were domesticated where they were found, or only brought into an area through trade.

Archaeologists have identified the regions where agriculture and animal domestication arose. These include Mesopotamia, China, Mesoamerica (Mexico and Central America), the Andes, Eastern United States, Indus River Valley in present-day Pakistan and India, California and Australia. The first region to adopt agriculture was probably Mesopotamia between 8500 B.C., followed by other regions such as the Indus River Valley in present-day Pakistan and India around 6000–3500 B.C.. Finally there are regions like California and Australia where European explorers introduced agriculture abruptly around 1750 A.D..

By the time most regions of the world had developed agriculture independently, they were already influenced by neighboring areas. The places that developed it first then got a head start on others in terms of guns, germs and steel.

Chapter 6

Humans began to cultivate the land around 8500 B.C. and not before that time because of a process of trial and error, which involved both agricultural practices as well as hunter-gatherer methods for several centuries until they finally settled on agriculture.

Over the last 10,000 years, it has become increasingly difficult to be a hunter-gatherer. Wild food sources have become scarcer and most of the world’s large mammal species have gone extinct. Another theory is that agriculture can support more people; humans were motivated to experiment with agriculture because it promised enough food for survival. Agriculture also depended upon technologies like hoes and awls that didn’t exist before about 10,000 years ago. So gradually, environmental changes and population density led humans towards agriculture as a way of life.

Chapter 7

Wild plants are often poisonous, and some cannot be eaten at all. But the idea of domesticating wild plants came from humans who figured out ways to make them edible.

There are many animals that help plants reproduce. Some of these animals eat the plants and then spread them to other areas by walking or flying away from the area where they ate those plants. Many of these animals digest the seeds before spreading them, but most of those plants still survive being digested by most animals.

Farmers didn’t understand genetics, but they did recognize that seeds could be planted and produce new crops. They also knew that if they planted the seeds of certain crops, those would grow into more crops with similar qualities as their parents’.

Almonds are an example of how humans have domesticated plants over time. Wild almonds are bitter and poisonous, but some varieties don’t contain cyanide. Humans eventually discovered those non-bitter almonds and replanted them in order to make more non-bitter almonds. This is true for many other foods as well: strawberries, mustard, poppies, lentils, etc.

Agriculture started in the Fertile Crescent of Mesopotamia, when people noticed how mutant grains didn’t pop out of their stalks. Therefore, they used these otherwise useless seeds to plant crops and create new generations of barley that was very unlike wild barley. Over time, humans’ preference for mutant grains that grew quickly led to domesticated barley and wheat that were different from wild versions of those plants.

Other crops, such as bananas and oranges, have been modified to produce fruit without the need for pollination. This process is self-pollination. Grapes are also hermaphroditic (they can be both male and female). They reproduce by fertilizing themselves instead of through cross-fertilization with another plant. Farmers started growing these plants because they were easier to grow than others that needed pollinators or cross-fertilization.

Throughout history, humans have domesticated many different plants. The first crops were wheat and barley, which are fast growing and easy to harvest. Later on, humans learned how to domesticate figs and olives—plants that grow more slowly than the first ones. Then they learned how to domesticate fruit trees through grafting. In short, humans learned to domesticate different plants at different times: by and large, across civilizations they began with fast-growing plants that were easy to harvest before moving onto slower-growing plants (if at all). By the time of the ancient Romans most of the world’s leading crops had been cultivated somewhere in the world

Some plants are impossible to domesticate. Acorns, for example, are bitter and not enjoyable to eat. This is why they weren’t domesticated in the past. However, almonds can be bred out of bitterness quickly due to a single gene being responsible for that trait.

Food is an example of evolution. Over time, crops have evolved to be sweeter and better tasting while growing faster. Charles Darwin even talks about this in the beginning of his book On the Origin of Species.

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Chapter 8

There are two major obstacles in the way of humans becoming farmers. The first is that they don’t want to experiment with domestication practices, and the second is that there aren’t enough wild plants to experiment with. Diamond will focus largely on the latter obstacle.

There are many plants in the world, but only a few of them are suitable for domestication. Most plants have no fruit or leaves that humans can eat. Even though modern times haven’t produced any new domestic crops, our ancestors figured out which ones were edible and which weren’t. Some people have access to certain fruits and vegetables that they’ve domesticated, while others don’t have those same products available to them or choose not to domesticate them.

The problem is that hunter-gatherer societies became agricultural ones only if they had a lot of crops to choose from and not just two or three. How, then, can archaeologists determine which areas are suitable for agriculture? Jared Diamond will try to answer this question by examining three different regions: Mesopotamia, New Guinea, and the eastern U.S.

Mesopotamia, or the Fertile Crescent, was an ideal environment for early farmers. The climate favored annuals—crops that sprout once a year. These crops were mostly edible and could nourish people. Mesopotamia also contained many hermaphroditic self-pollinating crops; i.e., they didn’t require cross-pollination from other plants to produce seeds every year and were protein heavy—they could feed humans well too.

Most of the world’s hermaphroditic crops are easy to farm and grow. Australia has similar climate conditions as the Fertile Crescent, but not many seeds; Chile, California, and Southern Africa have very few seeds. The Fertile Crescent is ideal for farming because it has a large number of different plants that can be farmed efficiently.

In the early civilization of Mesopotamia, people could rely on many different sources of nutrition. Cereals like wheat and flax fiber were good for carbohydrates, while animals provided dairy and protein. With agriculture came a surplus of food that was enough to support human life.

Diamond notes that he hasn’t talked about the superiority of Mesopotamian people, but rather about why agriculture succeeded in Mesopotamia. He has focused on the environment and how it influenced human beings. However, Diamond’s ideas rest upon an assumption: ancient societies had knowledge of their environments’ plants and animals. Therefore, it is unlikely that early farmers could have ignored a wild species with potential value to them.

Now Diamond will contrast Mesopotamia with the eastern U.S. and New Guinea, which is located in Oceania. In New Guinea, people were motivated to practice agriculture because there was no large game available for hunting and domestication of animals wasn’t possible due to lack of animals. Agriculture started around 7000 B.C., when people began cultivating sugarcane, bananas, taro and yams but didn’t have grains available (as there were in Mesopotamia). As a result of this diet that included only vegetables and fruits from plants such as sugarcane, bananas and taro, their bodies lacked certain nutrients necessary for health like proteins present in grains found in cereals grown by farmers in Mesopotamia or wheat grown by early settlers on the eastern coast of the United States.

In the eastern United States, agriculture arose around 2000 B.C.: farmers domesticated squash, sunflowers, sumpweed (similar to spinach), and goosefoot (also similar to spinach). Native American crops were extremely nutritious but had some problems. Sumpweed causes hay fever and skin irritation; it also has tiny seeds that make them unreliable as crops—a storm could destroy them. So even though the eastern U.S. had a good climate for agriculture, it wasn’t enough: the absence of resilient crops with big seeds and annuals resulted in limited agriculture in this region.

The chapter ends with some caveats. First, just because a crop is more nutritious doesn’t mean that people will automatically adopt it. Still, civilizations are more likely to develop sophisticated agriculture than primitive societies. Also, the order of domestication isn’t set in stone; although wheat and figs might be first on the list for easy crops, they’re not necessarily what’s going to be adopted first by a civilization.

Chapter 9

The chapter starts with the sentence, “Domesticable animals are all alike; every undomesticable animal is undomesticable in its own way.” The author is comparing how we define success and failure. In other words, he’s saying that our definitions of success tend to be narrow and specific. For example, if someone wants to succeed as a writer but doesn’t get published by HarperCollins or Random House, then they might think that they’ve failed at writing. But really, there are so many different ways for people to express themselves through writing—writing poetry on Tumblr blogs or publishing their own books online—that it’s silly for them to feel like failures just because some big publisher rejected their work.

Animals provide humans with food, clothing, and protection. Dogs also protect us while we sleep. However, only 14 species have been domesticated by humans over the past few centuries. These are the cow, pig, goat, sheep and horse.

The ancestors of our domesticated animals can be found all over the world, but not equally. For example, there are no large mammals in Africa that have been domesticated like those in South America. This strange phenomenon is due to the fact that African people do not travel to see large mammals as often as their counterparts from other regions of the world.

There are many reasons why Eurasian civilizations thrived. One of the main ones is that they had an abundance of large domesticable mammals, which were herbivores or omnivores weighing over 100 pounds. Europeans domesticated the horse and Africans never domesticed zebras.

One potential answer to Diamond’s question is that European culture made it easier for Europeans to interact with large wild mammals. However, Diamond rejects this explanation because there are many counter-examples: Africans today readily adopt domesticated pets; human beings’ fascination with animals; the fact that Africans in modern times have continued to try to domesticate animals and failed. The final piece of evidence is especially strong: in modern times, there have been attempts to domesticate elk, zebras, bison, etc.—and almost all such attempts have failed. There must be a biological (in the animals) or environmental reason for Africans’ inability to domesticate large mammals.

There are a limited number of animals that can be domesticated, and most large mammals don’t make the cut. The qualities of an animal that would make it easier to domesticate include being herbivorous or omnivorous (1), growing quickly (2), being comfortable breeding in captivity (3), not having a nasty disposition (4) and not panicking when they’re scared (5). If you put all those attributes together, then there are only about 14 animals on the planet which meet such qualifications—the 14 animals that have been domesticated since ancient times.

Chapter 10

The continents of Earth are different in many ways. Most of them have a wider north-south span than they do an east-west one. This means that their major axis is the north-south one, and this affects how civilizations develop on those continents.

In history, agriculture spread from certain areas to others. It’s estimated that it spread east and west much more quickly than it did north and south. For example, agriculture spread from Mesopotamia to the Indus Valley at a rate of almost 1 mile per year (but in the Americas, it only spread north from Mexico at 0.3 miles per year). In general, innovations in food production—from agriculture to domestication of large mammals—spread more slowly through the Americas than through Eurasia. Why?

Agriculture spread from Mesopotamia to Europe. Europeans learned how to domesticate wild plants in their regions by imitating their neighbors, but the truth is that they acquired new crops from the east through trade and travel.

The main point is that latitude (the measure of how far a location is from the equator) determines climate better than longitude (the measure of how far east or west a location is). This is because Earth rotates on an axis, meaning that the sun’s heat warms places with the same latitude equally. Two areas with the same latitude will tend to have very similar climates, even if they’re on opposite sides of the world.

Eurasia is unique among the continents in that it’s longer from west to east than it is from north to south. Therefore, there were more areas of Eurasia that shared latitude than there were in Africa or the Americas. Mesopotamian agriculture spread quickly because many different peoples benefitted from it and its climate was similar. However, this didn’t happen with other cultures like those of the Incas who couldn’t transport their domesticated animals north into Mexico due to a barrier created by changes in climate.

Caveat: Similar climates don’t necessarily occur in areas with the same latitude. For example, crop innovations never reached the southeast of America even though they had the same latitude as other regions because most of that land was not suitable for farming.

He suggests that one could study the spread of ideas in general, not just crops or domesticated animals. For example, writing was developed in Mesopotamia and then spread to Rome and India (same latitude), whereas writing never spread to the Andes (same longitude).

Chapter 11

So far, Diamond has addressed how differences in environment led to differences in food production. He will now show how agricultural differences between civilizations led to vast differences in literacy, health, technology and government.

A farmer once tried to have sex with a sheep, caught a disease from the animal and was left in terrible shape. Few people would try to imitate him, but living close to animals can lead to diseases.

Germs and viruses have caused a lot of deaths in human history. Many plagues and epidemics, like the Black Death, Spanish Flu, have been caused by diseases that spread from animals to humans. From the microbes’ point of view, there are certain strategies they can use to pass on their disease from host to host. Microbes have evolved so that they can move through saliva and other bodily fluids; provoke reactions like bleeding or vomiting; anything that passes them onto another host (even if it kills them).

Humans have a few ways to protect themselves from germs. For example, they can cough or sneeze to get rid of the germs in their body. Another way is for them to have an immune system that kills off the germs. But over time, humans who aren’t as strong against diseases are more likely not to survive and reproduce, eliminating those genes from the population. This is evolution at work: because of this process, people today are generally immune to diseases. Therefore, when disease-causing organisms evolve new traits that allow them to infect people better than before, it puts our bodies under pressure and makes us develop stronger defenses against those pathogens.

A small community, such as a hunter-gatherer one, might not be able to survive certain diseases because they would either 1) die off quickly or 2) develop immunity. However, there are some diseases that can only survive in larger communities like those of 500 people or more. These include measles and other infectious illnesses that need many hosts for them to live on.

Agriculture and the rise of cities led to crowd diseases. As agriculture advanced, people were more sedentary and had greater access to shared resources like food and water. The same was true for city life; as populations grew in urban centers, so did their exposure to shared resources.

Agriculturalists are more likely to suffer from infectious diseases, but because of their large populations, their communities will also be more likely to survive those diseases.

European explorers who came to the Americas brought diseases with them. These diseases killed many Native Americans because their immune systems had no defenses against those illnesses. One reason for this lack of immunity was that Native Americans hadn’t interacted a lot with domesticated animals, while Europeans hadn’t interacted with certain New World diseases such as yellow fever and malaria. However, despite these infectious disease deaths, European colonizers benefited from these infections because they were more resistant than the natives to these illness-causing pathogens.

Chapter 12

In this passage, the author will discuss why some civilizations developed writing while others did not. He’ll focus on four key agents of colonization: weapons, microbes, writing and centralized government.

All writing systems have three different parts. The first part is the alphabet, which uses signs (letters) to stand for sounds in a word. The second part is logograms, which are used to represent whole words with only one sign. Finally, syllabaric languages use signs that represent syllables of words—they are now very rare but were once common.

It is known that the Sumerians, Mesoamericans, Chinese and Egyptians developed writing independently. The Sumerians were the first to develop it; they did so around 3000 B.C. Their language combined aspects of alphabetic, logogramic and syllabaric languages. They used pictures to represent individual syllables in words; this would be like an English speaker seeing a picture of a bee followed by a leaf and pronouncing the word “belief.”

Ideas spread from civilization to civilization in two ways: blueprint diffusion and idea diffusion. The Roman alphabet (A, B, C…) was copied from the Semitic alphabet but it did not perfectly replicate it because each language has its own modifications on a previous one.

There are many cases of idea diffusion throughout history. For example, the Cherokee developed a written language based on their knowledge of English. They experimented with pictographs but eventually settled on syllabic characters to represent all spoken words in Cherokee. There are other examples of civilizations developing languages inspired by another civilization’s language.

Despite the fact that we can’t be sure of why some civilizations developed languages while others didn’t, it’s important to recognize that the earliest languages were not as advanced and efficient as today’s modern languages. Many words in cuneiform had multiple meanings or interpretations, depending on context. However, this was not a problem for scribes and scholars who used cuneiform to keep track of taxes and debts: which people owed what goods to people in power.

From the history of cuneiform, we can see that writing was invented to keep track of economic transactions in a large agricultural society. However, it’s not enough for a society to be agricultural and large; it must also have writing.

Most civilizations acquired writing by interacting with other civilizations that already had it. Therefore, a major reason why certain civilizations had writing while others did not is because they were close to those who already did and could pass on their knowledge of how to read and write. Writing spread in an east-west direction faster than north or south due to the Sahara Desert isolating West Africa from North Africa.

Chapter 13

The Phaistos Disk is an ancient clay disc with stamped images on it. It’s not clear if the Minoan language was indigenous or borrowed from a neighbor, but historians have been unable to decipher it because of its uniqueness. The disk also represents how difficult it can be to understand why certain technologies were invented in certain places at certain times. Inventions are unpredictable and idiosyncratic, so why was printing first invented by the Minoans?

The history of technology is a subject that has been debated by many. There are several schools of thought on how and why technology develops. One theory suggests that the development of new technologies is due to single “heroic” figures, like Archimedes or the Wright Brothers, who make breakthroughs in their respective fields. However, this theory neglects the fact that multiple people were involved in developing any one object (for example, there were at least a dozen people who helped invent the steam engine). Technology evolves over time as more and more ideas come about from different sources.

Another theory is that necessity is the mother of invention. If a society needs something, someone will figure out how to build it. However, this idea has problems because inventors often don’t realize how their own inventions can be used. The car engine and phonograph were developed for purposes entirely different from those with which we now use them. So in a way, invention comes before necessity; technology finds uses after it’s invented instead of being invented for a specific purpose.

The driving force behind the discovery of new technologies is experimentation. People start with certain materials and try different things to discover new things, like glass. The same was true for gunpowder: people mixed together sulfur, saltpeter, and charcoal in order to create a new substance.

After a new technology is discovered, it has to be popularized. There are several factors that influence the popularization and acceptance of such a technology: 1) economic benefits, 2) social prestige, 3) ease of understanding its advantages and 4) compatibility with vested interests. For example, Britain used gaslights in the 1920s because they were already invested in using them.

Historians of technology have found that there are many factors that influence whether a society will adopt new technologies. For example, societies that protect intellectual property and tolerate different religions might be more likely to accept new technologies than those who don’t. However, the question remains: why do some cultures embrace technological change while others reject it? Jared Diamond aims to answer this question by examining these cultural differences in his book “Guns, Germs, and Steel”.

Technology usually arises from the use of natural resources. However, there are many instances where technology is not based on any raw materials, such as writing. There are also inventions that arise in certain civilizations but not others with similar resources (such as compasses and windmills).

The exchange of technology can happen in two ways. First, there is the diffusion of a blueprint that can be used to build a specific product (e.g., blueprints for manufacturing airplanes). The second way is to diffuse an idea and let people figure out how to use it themselves (e.g., the invention of computers). Societies differ in how readily they can receive technologies from other societies; some are more geographically isolated than others, making them less likely to acquire new ideas from abroad.

Additionally, isolated regions are more likely to permanently abandon technologies. For example, Japan abandoned foreign imports like guns after the 1600s due to xenophobia (fear or hatred of foreign cultures). Societies that have been geographically connected over time will be more likely to reacquire a technology than ones that have been geographically separated for longer periods of time.

Technology is self-catalyzing, which means that once a technology has been discovered, it can lead to the discovery of other technologies. For example, pottery led to metallurgy because people needed metal tools and weapons to make their pottery. Technology leads to more technology.

In his paper, Diamond talks about how the Minoans didn’t succeed in popularizing the printing press in Europe. He reasons that this is because their technology was slow and clumsy and it wasn’t much better than writing by hand. Furthermore, at the time of its development, there weren’t many people who could read or write so they couldn’t take advantage of a new medium like print.

There are two major jumps in technology. The first occurred 100,000 years ago when people started making tools out of bone and stone. The second jump was the adoption of agriculture 13,000 years ago. Agriculture led to a sedentary lifestyle and centralized societies with large populations.

The three major factors that have led to the development of technology are “time of onset of food production, barriers to diffusion, and human population size.” Eurasia has more people than any other landmass and is longer from east to west. The Fertile Crescent in Asia also contains a lot of people along with two centers for food production. There aren’t many geographic barriers in this area, either. As a result, technology arose earlier here than it did elsewhere on earth and diffused faster as well. All these advantages helped maintain technological supremacy over other continents even centuries later.

Chapter 14

The Fayu are a nomadic group of people in New Guinea. They live in small families and only get together occasionally. The reason for this is that they’re violent towards each other, so it’s safer to avoid large groups. This type of lifestyle was common among humans until about 12,000 years ago when centralized government and religion began to develop as a result of the need for protection from outside forces such as predators or enemies.

Diamond will discuss four types of government: bands, tribes, chiefdoms and states. These are broad categories that don’t always fit neatly into one category or another. Still, they’re useful for approximating how different governments evolve over time. A state is a government with more than 50,000 people divided between several towns or cities with a centralized bureaucracy and written laws to solve problems.

A band is a group of nomadic people who don’t have any complex bureaucracy or specialization. They all hunt and forage for food, and there are no true classes in bands, as they have leaders who distinguish themselves with their strength and intelligence. One example of a band is the Fayu Jive of New Guinea.

A tribe is a group of people who live in one place and know each other well. Because they are so close, conflicts can be resolved by talking to the person involved instead of going to court. Tribes do not need laws because everyone knows each other and social pressure maintains order. Examples of tribes include the New Guinea highlanders.

Chiefdoms are very complex societies, and they differ from tribes in that the people don’t know each other personally. The chief is responsible for solving all disputes, so he or she is an important figure in society. Hereditary chiefs usually rule a chiefdom, and beneath them there are many different classes of people who do various jobs to support the tribe—artisans, hunters and gatherers, etc. People pay tribute to their leaders by giving them gifts such as food or luxury items like jewelry.

A chiefdom is a society in which the leader receives money from his or her followers. The leader can use that money either selfishly for himself or to help the people of the chiefdom. A kleptocracy (a government that steals its citizens’ wealth) could be said to exist in a chiefdom, but at the same time, a benevolent leader might use taxes collected from his people’s labor to build public works that benefit everyone in society.

Diamond argues that kleptocratic leaders have to make a choice: they can either control their people and deprive them of wealth, or spend the money on popular programs in order to keep the people happy. Kleptocrats try to convince their citizens that paying taxes is worth it because they get some kind of service in return.

Kleptocrats use other ways to encourage their people to follow them. They create religions that justify their power, and they spend much of the tribute money on religious buildings. By popularizing religion, kleptocrats not only gain respect from their followers; they also convince them to sacrifice for their chiefdom in times of war.

The last type of government that Diamond will discuss is a state. Most people are familiar with states, which use democracy to elect officials. Even though these elected officials have the most information and power in a state, they also rely on citizens for help. In addition, states redistribute wealth more than chiefdoms do and require citizens to be specialized enough that almost no one can survive alone without help from others.

Early states had more social hierarchy and specialization than chiefdoms. People who served the state government had different levels of power, as well as a variety of departments, such as law or taxes. Early states also tended to have strong religious traditions with the king often considered a divine being.

Over the last 10,000 years or so, there has been a trend of forming states and eliminating tribes. States are more powerful than other forms of government because they have large populations with military specialization, patriotism that motivates citizens to fight for their rulers and die for them, and religious fervor that didn’t exist before the rise of chiefdoms/states 6,000 years ago.

For a long time, people have tried to understand how states arise. Some argued that it’s inevitable for us to gather together and form a state; others claimed that we agree to form the state in a process called the social contract. Both of these theories have been disproven over the years: there are many forms of communities other than states, and humans literally never agreed to form a social contract either.

There are many theories that suggest a correlation between the size and density of a population and the formation of an organized state. However, it’s not clear if this is cause or effect.

One of the reasons why complex societies develop is because they have a lot of food. It’s not just that people need to eat; it’s also about storing food and having enough time to work for the government or do something else. Agriculture allows people to live in one place, which means they can gather more resources and experiment with technology and crafts.

States are by far the most efficient form of government for large societies. They’re more effective than bands because they have four main advantages: 1) in a society with hundreds or thousands of people, no one knows everyone else; therefore it’s difficult to use kinship structures to resolve conflicts, 2) it’s impractical for everyone to make decisions about what needs to be done as in a band or tribe, 3) trading goods directly with others is inefficient compared to using central authorities who can keep track of which resources belong where and 4) large groups need access to more space per person than do small groups. Therefore, they depend on other people who may have better access. For example, if there were 20 people within 5 square miles (100 acres), then each person would essentially have the same amount of space and resources available as anyone else. However if there were 100,000 people living within that same area (5 sq mi), certain individuals might have better access while others would not. This leads towards specialization and states work best when run like kleptocracies.

How does a small society become a large state? It’s largely due to natural selection. The most stable and organized bands survive, while the weaker ones collapse or die out. In addition, strong bands stand a better chance of defeating other bands, leading to larger societies. Essentially, tribes either die out or conquer others and grow larger over time. There are also times when tribes merge voluntarily – for instance in 19th century America Native American tribes merged to form the Cherokee state.

Diamond raises a question: if people have always fought one another, why didn’t they form large tribes before 13,000 years ago? The answer has to do with the fate of tribes after they’ve lost a war. In general, defeated tribes 1) run away to new territory when population densities are low; 2) are murdered when population densities are moderate; or 3) are enslaved and put to work when population densities are high. Therefore, it wasn’t until the agricultural revolution that higher populations led to larger states.

To conclude, differences in the level of development of civilizations can be traced to factors such as “food production, and competition and diffusion between societies.”

Chapter 15

In Australia, it is so hot and dry that it seems impossible to survive. However, aborigines have managed to do just that. Indeed, they survived in Australia even though they had no agriculture or technology. When Europeans explored the area, they found aborigines still using stone tools and making cave paintings 40 thousand years ago (well before any other group of humans around the world developed stone tools or painting). Why did the aborigines remain “frozen” in the Stone Age instead of taking advantage of their “head start”? Furthermore, why did New Guineans near Australia develop agriculture and elaborate technologies while Australian aborigines didn’t?

Humans are believed to have been in Australia 40,000 years ago. At that time, Australia and New Guinea were probably one large landmass called “Greater Australia.” However, with changes in sea level, the two landmasses separated into distinct geographies. The Australian and New Guinean people diverged genetically and physically because of natural selection due to their different environments.

The earliest known farming regions in Australia were found in New Guinea about 9,000 years ago. The people of New Guinea used their farming techniques to domesticate sugarcane and grass stems. They also acquired foreign exports from Asia like pigs and chickens around 4,000 years ago. This agricultural boom led to population growth and density which fostered social specialization such as artisans who made stunning wooden statues and masks for the community.

There are many differences between the aborigines and the New Guineans. The aborigines had no domesticated animals, which allowed them to have more leisure time for specialization in their skills. They also lived in a larger area with more space for population growth. Since they were able to grow crops at lower altitudes than the New Guineans, there was a greater need for trade and exchange of goods among different communities specializing in different crops.

Australia had limited agriculture and no domesticable large mammals. Its climate was irregular, which made it difficult to predict droughts. Finally, Australia didn’t have a lot of wild plants that could be grown for food. Therefore, the aborigine culture in Australia was based on hunting and gathering rather than farming or ranching.

The aborigines lived in the southeast, where it was humid. They fished for eels and fish in the rivers there. They even harvested millet seeds, which were a staple of agriculture in China but which they harvested wild and ground up into meal without planting them first.

The aborigines did not develop advanced technologies because they had no agriculture. They might have had complex technologies and forgotten about them, similar to the Japanese forgetting about guns. Evidence of bone needles and arrowheads suggests that the aborigines once had advanced tools but abandoned these for simpler ones.

Why didn’t Australia acquire advanced technologies from Indonesia or New Guinea? Diamond asks. The two regions were connected via the Torres Strait, but geography prevented major cultural diffusion into Australia as a whole.

In the 1500s, Portuguese explorers “discovered” New Guinea. Over time, European colonists explored it. They didn’t wipe out the indigenous population in Australia or North America as they did in South Africa and parts of India. Why?

New Guinea was difficult to settle because of disease, terrain, and crop failures. New Guineans spread malaria to the Europeans living there, which killed a lot of them. However, they were not affected by European diseases like smallpox due their prior exposure to those diseases through contact with Indonesians and Southeast Asians. The terrain in New Guinea is rugged and hard to navigate; therefore familiar crops did not grow well there.

Europeans settled Australia more easily than New Guinea. The land was easier to navigate and less infertile, so they had the incentive to settle there. They also didn’t have as many diseases that could slow them down in their progress.

In conclusion, Australia and New Guinea used to be a part of the British Empire. People often assume that white settlers were better than the native peoples they abused. However, Europeans who settled other parts of the world had some advantages over Australians and New Guineans. They had more advanced technology because they were closer to Europe and its resources.

Chapter 16

China is often considered one of the most politically and culturally monolithic countries in the world. For example, they have been united under a single government since 221 B.C., and almost all Chinese people speak Mandarin, which is only one of many languages that are related to it. However, how exactly did China become “Chinese”—or rather, how did China stay Chinese for so long?

China is culturally monolithic despite the geographic differences, which makes it surprising. Northern China’s climate is much colder and drier than Southern China’s, but that doesn’t mean there are half a dozen different states in China with their own cultures and languages.

Let’s look at the Chinese language. There are eight “big” languages spoken in China, all closely related to Mandarin. But there are also hundreds of “little languages,” spoken by thousands or tens of thousands of people. Many little languages are structurally linked to modern-day Thai and Cambodian and Lao language groups. Further linguistic history indicates that the earliest speakers of Mandarin lived in Northern and Southern China. Often a new language replaces another one because powerful warriors or colonists spread their own language into other regions, pushing out other ethnicities with their own tongues. So really, what allowed Mandarin-speaking Chinese peoples to drive many other ethnicities into surrounding Southeast Asia?

In ancient times, Chinese people were farmers. They grew rice and millet in a temperate climate. In addition, they had access to many large mammals that could be domesticated for labor purposes. As Diamond has discussed earlier on, the discovery of metallurgy and other sophisticated technologies led to social hierarchies as well.

China is a large country with many regions. People in all of the regions had access to agriculture and were able to travel north or south easily, thanks to China’s rivers. As a result, Chinese people learned from one another and adopted similar technologies such as rice cultivation, writing, and ironwork. Most of these technologies diffused from north to south but some diffused from south to north. This caused ethnic Chinese people throughout China (from the north and the south) to be culturally unified.

The formation of a Chinese dynasty began in 221 B.C. One reason for the unification of China under one state was cultural: The northern and southern Chinese, with their similar technologies, united because they shared many of the same cultural beliefs.

The Chinese were able to unite and overcome their differences because of rivers, which made it easier for them to communicate. The ethnic Chinese drove out other cultures in China and burned books that weren’t written in Chinese. Because of this, the culture became increasingly monolithic over time.

Chapter 17

In New Guinea, ethnic tensions remain high. People from the center of New Guinea have stereotypes about people on the coast and vice versa. The center is said to be arrogant while the coast is weak.

About 6,000 years ago, there was a demographic shift called the Austronesia expansion. People in China and Southeast Asia migrated farther south to explore the islands of present-day Java, New Guinea, and Indonesia. It’s important to ask why Asians colonized indigenous Javans and New Guineans instead of the other way around.

It is important to note that the populations of Indonesia and the Philippines look like southern Chinese people, more so than they resemble indigenous peoples in Australia or New Guinea. Archeologists have found evidence that suggests Austronesian cultures were hunter-gatherers until about 4000 B.C., when agriculturalists from Taiwan began to migrate throughout Austronesia. Agricultural techniques spread with them, as well as domesticated animals and pottery. The first explorers 6,000 years ago probably used small boats or canoes to travel through Austronesia. So today’s Austronesians (people in Java or New Guinea) are probably descendants of those early agriculturalists who migrated thousands of years ago.

Studying languages helps linguists figure out the cultural diffusion of peoples. By looking at similar words in different languages, one can guess that people from those cultures were trading with each other or spreading their ideas and technologies to others. For example, it’s likely that Spanish, Russian, Greek and Lithuanian speakers traded sheep with one another because they all have a word for “sheep” that sounds very much alike. The fact that Polynesian languages share similarities with Taiwanese ones suggests that agriculturalists spread their crops through Austronesia (the Pacific islands) from Taiwan around 2000 BC. Along the way they also added tropical crops to their repertoire of food-growing skills.

Agriculturalists expanded from Taiwan into the Philippines and Indonesia. They reached New Guinea by about 1500 B.C., but they didn’t take over the island, as they did in other places like Borneo, Sumatra and Java. This is because of differences between the people of Java versus those of New Guinea. The modern-day population speaks languages not found in Java or Sumatra—languages that aren’t closely tied to ancient Austronesian languages.

Diamond proposes that the reason why New Guinea was not colonized by Austronesians is because it had already been partially developed in terms of agriculture. The natives were also resistant to tropical diseases, and thus had a better chance at survival than those native populations on other islands.

Civilizations that have the technology and organization to colonize other parts of the world are based out of temperate climates. In ancient times, Southeast Asian societies were able to expand their control into areas like Hawaii, New Guinea, and Caledonia because they had tropical diseases or agricultural problems in those places. Today, East Asia is still populated by East Asians but not European colonists.

Chapter 18

Now, Diamond discusses the clash between Europe and the New World. This began after 1492 A.D., when Western European society was different from Native American societies that Columbus encountered in the New World.

It’s true that Native Americans didn’t have domesticated animals. That was one of the reasons why they weren’t wiped out by European diseases, unlike Columbus and Pizarro.

First, the New World had fewer agricultural opportunities because of its geography. In addition to that, Native Americans were hunter-gatherers because they didn’t have fertile soil or sources of grain like Western Europe did. There are also geological barriers (mountains and deserts) that prevented agriculture from spreading in the New World, which gave Western Europe an advantage over it.

Archaeological evidence shows that Eurasia had an advantage over the New World when it came to the development of civilization. In Eurasia, civilizations mastered plant and animal domestication, metallurgy, and writing before civilizations in the New World. This was based on research conducted by Diamond—he acknowledges that there is conflicting archaeological evidence but he simplifies it greatly. Nevertheless, archaeology would support his conclusions about this topic.

In the New World, agriculture, technology and writing diffused slowly because of geographic barriers such as mountains and deserts. For example, llamas didn’t spread to Mexico because they would have had to walk hundreds of miles through dangerous deserts. However, in Eurasia there were fewer physical barriers so diffusion was relatively easier than in the New World.

The first large-scale attempt to colonize the New World was made by the Vikings. They traveled to Newfoundland and Greenland, but failed to go farther west or south. The colonies they established in these territories are mysterious; it appears that they died off sometime before 15th century because Newfoundland and Greenland weren’t suitable for agriculture.

Europe’s second attempt to colonize the Americas was after 1492. The expeditions spread germs which killed off huge numbers of Native Americans. Since 1492, there has been a massive demographic shift in the population of the Americas—there remains only about a tenth of the Native American population that existed before 1492 (although the total population of the New World has grown considerably). For environmental reasons Diamond lays out, this massive demographic shift post-1492 “has its ultimate roots in developments between 11,000 B.C. and A.D. 1.”

Chapter 19

Africa is extremely diverse. It has many different languages and people groups, as well as the five major divisions of humanity.

Africa is home to five different human races: blacks, whites, African Pygmies, Khoisan and Asians. However, even with these races being grouped together as one race it can be problematic because of the great physical and cultural differences between them. The grouping of these races serves as a useful way to understand history though.

In this passage, Diamond offers physical descriptions of the five races he will discuss. Blacks and whites are familiar to Americans and Europeans. Pygmies and Khoisan live in sub-Saharan Africa. Asians inhabit Madagascar, which is anomalous because its population is largely descended from Southeast Asians (i.e., the people who live in Borneo, the Philippines or Polynesia).

Linguists have found that Western culture did not originate in the Near East. In fact, it originated in Africa and was passed down through Semitic languages.

Another surprising discovery that linguists have made is that the Bantu language family in Africa originated from North Africa. The Khoisan and Pygmy peoples were swallowed up by the Bantus, rather than vice versa. This happened because of their superior culture and technology at the time.

Diamond talks about the food sources in Africa before Europeans colonized it. He mentions that Africans only had small domesticated animals, such as guinea fowls and sheep. They did not have any large mammals like cows or horses. The crops they grew were also imported from other regions, such as bananas and millet. Diamond concludes that most of Africa’s food came from outside its borders long ago.

The Bantu language family is spread throughout Africa. It’s believed to have originated in the Nile Valley, but there are some clues that suggest it started in the Sahara. Archaeological evidence indicates that 11,000 years ago, people living in what is now the Sahara spoke four languages ancestral to modern African languages.

Before we trace the history of Bantu and Khoisan any further, let’s look at Madagascar. How were Austronesians able to travel there? Ancient texts written in Egypt describe a large sea trade between India and Egypt after Islam rose. It is possible that Austronesian colonists traveled along the Indian Ocean trading network to Madagascar, bringing with them artifacts from their Southeast Asian culture.

The Bantu expansion was one of the largest demographic shifts in African history. Prior to the Bantu expansion, most people were not black peoples. After 1000 BC, though, the number of Bantu peoples grew so large that they expanded southeast and developed new farming techniques to incorporate new crops like millet into their agriculture and iron metallurgy which gave them an unbeatable military industrial package.

The Bantu expansion resulted in the genocide of the San and Pygmy people. Although it’s unclear what role diseases played, malaria may have killed a large number of them since they were not resistant to it. It’s important to note that although these groups were killed off, there are still some remaining in southern Africa because their areas are unsuitable for farming.

A question that arises is why Europeans colonized Africa instead of Africans colonizing Europe. Europeans had many advantages over the Africans, including access to better technology and immunity from diseases. The reason for this was because Europe had domesticable animals and plants, as well as centralized societies with advanced technologies. Sub-Saharan Africa did not have these things, which prevented them from developing their own colonies in other parts of the world.

In conclusion, Europe’s colonization of Africa had nothing to do with racial superiority. It was due to a series of geographic coincidences that the Europeans became stronger and more mobile than the Africans, going off on their own “historical trajectory.”


According to Diamond, the answer to Yali’s question is this: differences in people are not due to innate differences. Rather, it’s because of the environment that they live in.

The world is different because of four factors that influence human history. One factor is the availability of wild plants and animals to be domesticated. Another factor is barriers, which can stop people from migrating or diffusing technology between continents. A third factor is barriers, which prevent diffusion and migration between countries within a continent. Finally, the fourth factor is population size and density in each country. These factors are important in determining how successful a society will be with its food supply, health levels, technological development, political organization (centralization), immunity to disease (like smallpox), and more..

There are some caveats to Diamond’s conclusion. He doesn’t talk about all of human history, which is impossible for one book to do.

Diamond’s conclusions are valid, but there are some exceptions. For example, China and the Fertile Crescent had comparable advantages in geographic factors. Why did Europe overtake these regions? Specifically, why was it Europe that developed mercantile economies and capitalism as a result of exploration and technological research?

The Fertile Crescent lost its advantages over time. It became drier and the soil was less fertile, which made it less productive than other parts of Europe.

Why was it Europe, not China, that became a world leader in the late 15th century? One would think that China’s huge technological innovations (the compass, printing, gunpowder) and sophisticated navy would have made its global influence and domination inevitable. Yet China mostly gave up its maritime expeditions in the middle of the 15th century. The Chinese government decided to withdraw from exploration for 400 years because of political stability. This allowed Europe to dominate new territories without any competition from China.

In Europe, the political unification process was much slower than in China because of its geographical fragmentation. For example, China has many rivers that connect it together and make it easier to travel around. However, Europe consists of large islands and mountains with small rivers which don’t connect all of the continent together like in China. Therefore, there were more squabbles in Europe as a result of this lack of unity due to competition between nation-states. This is why Western European countries invested so much money into exploring other parts of the world—they wanted to be ahead their rivals during colonization (colonizing new territory).

Another important point is the role of culture in history. Although Diamond’s book mostly focuses on environmental factors, it does not take into account cultural differences between different peoples of the world. This is an important topic that should be explored further.

Diamond’s conclusions don’t account for the actions of individuals. Sometimes, a single person can change the course of human history, like Lee Harvey Oswald (who assassinated President John F. Kennedy). This doesn’t seem reducible to geographic causes. Diamond concludes that it remains an open question how wide and lasting the effects of idiosyncratic individuals on history really are.

Throughout the book, Diamond has tried to use a scientific approach in studying history. However, he acknowledges that there are some differences between science and history. In science, you can isolate an independent variable by controlling for other variables, but it’s more difficult to do this in history because of the complex nature of its data. Therefore, historians should look at civilizations that have similar environments so they can better isolate causes and effects.

Guns, Germs, And Steel Book Summary, by Jared Diamond Ph.D.

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