This is my (long) summary and comments for Crop Histories, by Raoul Robinson.
Overall I really enjoyed this book. It’s a fun and fascinating read all about human history and our crops, and might serve as a primer to some of his other more technical works. Raoul has a funny, conversational tone; he might be a bit biased at times, and I can tell what themes and crops he is personally excited about. But I learned lots of specific details about individual crops, and also the bigger-picture trends in human agricultural history. I’m excited to move into his more technical work about plant breeding and horizontal resistance.
I’d love to hear any comments or discussion from others who are interested in Raoul’s work.
Overview
2007 Edition, first published in 1996.
Raoul Robinson (1928-2014) was a Canadian/British plant scientist with more than forty years of wide-ranging global experience in crop improvement for both commercial and subsistence agriculture.
Crop Histories is an overview of the complex interaction between human development and our relationship to our food crops.
Part One gives history of humanity’s transition from wild ecosystems to agro-ecosystems with domesticated species capable of supporting civilization. Raoul’s main thesis is that agricultural success in domesticating staple food crops is the main driver in the development of civilization and culture. He argues that staple crops have directly and indirectly allowed us to dramatically increase our populations, but we will ultimately need to stabilize our natural tendency to overpopulate or face starvation.
Part Two details the history of the world’s three staple food crops: wheat, rice, and maize. Raoul argues that the development of civilization depends on the presence of one of these three crops.
Part Three details other crops that shaped history, including coconuts, spices, potatoes, rubber, tea, coffee, cocoa, cotton, sugar, tobacco, bananas, alcohol, and drug-producing plants. The book concludes with a brief section looking toward the future.
Chapter 1 - The Wild Ecosystem - Raoul outlines his goal of examining “history from the point of view of a biologist, and ecologist, and an agriculturist.” He says that “without crops, there would be no civilisation, no perceived history, and no historians.”
The Importance of Grass - The evolutionary arrival of the grass family had a profound effect on mammalian evolution, and is essential to the evolution of humans. Without grasses, mammal evolution wouldn’t have exploded, humans wouldn’t have evolved, and without cultivated grasses, there could have been no development of agriculture and no civilization.
The Carrying Capacity of the Environment - Before modern human evolution, our wild ancestors could eat many plants and animals, but couldn’t eat grasses. “Carrying capacity” is the strict limit in the amount of food that a wild ecosystem can produce, which restricts the size of a population. A hominid population that increased beyond the carrying capacity had three alternatives;
surplus hominids die,
territory is expanded through war with neighbors,
or migration to another uninhabited area. The pressure to migrate became so strong that virtually every habitable place in the entire world was colonized.
Three Brutal Laws of Nature - Evolution could not occur without the three brutal laws of nature: carrying capacity is inherently limited, the livable environment is a finite, limited area, and all species reproduce in excess of their carrying capacity, because under-population is inherently disastrous for species survival. In other words, resources are always limited, so nature leads to “survival of the fittest”, or more accurately, “elimination of the least fit”. This struggle for existence is the driving force behind evolution.
The Hunger Compulsion - Raoul argues that hunger is the most compelling of all motives. Because populations will always grow beyond their carrying capacity, the surplus population will always face hunger, which means death, war, or migration. The necessity of preventing and eliminating hunger and the fear of hunger has led to human domination of our environment. Intelligent beings have three additional alternatives to vanquish the three brutal laws of nature. 1. Use intelligence to increase carrying capacity, 2. Use intelligence to make an inhospitable environment tolerable, or 3. Use intelligence to restrict the growth of the population.
The First Alternative - Modern humans were the first species to significantly increase their carrying capacity, first by becoming meat eaters, using stone tools, and hunting and scavenging cooperatively. Later they discovered and tamed fire, which also increased carrying capacity through the development of cooking food. Food variety, digestibility, and nutritive value increased. Food pathogens and parasites were controlled through cooking, and fire protected against wild carnivores. Many people became herders, first living with wild herbivores, then becoming mutually dependent as people protected the herd in exchange for food and animal resources. Ten thousand years ago, the world population became so large that there were no unoccupied areas left to colonize, but intelligence enables dramatic new increases to carrying capacity, including through the invention of agriculture.
The Second Alternative - Despite hunting and meat-eating, humans still reproduced in excess of the carrying capacity. Hunger once again forced humans to migrate out of tropical Africa into temperate Europe and Asia, which required the invention of building and clothing, and use of fire for warmth. Caves were popular wild shelters, but were not common and numerous enough. First buildings were temporary primitive structures made from sticks and animal skins. Permanent buildings were not needed until the discovery of agriculture. Special rituals developed to maintain fires and prevent them from going out. Ability to survive cold dramatically increased the total environment available, as huge temperate regions became tolerable.
Migration into the Americas - During the last ice age, most of northern North America was covered in permanent ice, making migration to the New World impossible. However, there was probably an ice-free corridor that connected Alaska to more hospitable areas. The only alternative theory to land-bridge migration to North America is that early colonizers came by sea in skin boats, scavenging along seashores for food. In any case, these colonizers were still hunter-gatherers dependent on a limited carrying capacity.
The Third Alternative - Despite overcoming the first two brutal laws, we are being defeated by the third; we still reproduce in excess of our carrying capacity and there is no unoccupied, habitable land left to colonize. During the twentieth century, world population increased from 1.5 billion to 6 billion, requiring a quadrupling of agricultural production. Agriculture production has massively increased but we are again reaching the limits. Over-population and hunger are still the most important problems humans face. If we do not stabilize our population growth, billions will likely die of starvation. Raoul believes the only alternative left to us is to control the size of our population, which may be aided by contraceptives, and perhaps a new ethic of restricted reproduction.
The Thirst Compulsion - Raoul argues the need for water is more vital than the need for food, but that water has historically been more plentiful than food, and usually not a limiting factor. But in the modern era, total supply of clean water is decreasing and could become an important factor.
Starvation - Raoul concludes the chapter with some dramatic flair, with more discussion of the agony, tragedy, and despair of starvation.
Chapter 2 - Domestication
The Environment - Development of civilization depended entirely on quality of the local environment, and not the quality of the humans who inhabited that environment. More specifically, civilization arises from the domestication of wild animals and plants, which some areas do not possess.
Cultural Evolution - Darwinian evolution is based on genetics, cultural evolution is based on memory. Cultural evolution occurs in some, but not all social species. A social memory can survive and grow from generation to generation, and live indefinitely. Although wild primates, dogs, rats, whales, dolphins, and others have proto-cultures, humans are the only species that has developed major cultures. Our cultural developments began very slowly over two million years ago, but have been growing ever since at an exponential rate.
Domestication -Domestication is the replacement of natural selection with artificial selection. A strong selection pressure can change a population out of all recognition within only a few generations, but usually wild populations change slowly because they are in balance with their environment, change is unnecessary, and the selection pressures are slight. Domestication is often unconscious, occurring by simply selecting the best individuals to become parents. Dog breeds are a helpful example because they show how many ways a wild species can be changed in order to fulfill many different functions.
The Domestication of Animals - The first domestication involved animals, and occurred mostly in the Old World because the New World generally lacked wild species suitable for domestication. Ancient people began to live in association with herds of wild herbivores, and eventually became herders, protecting the herd from wild carnivores and in exchange using animals for meat, milk, blood, and tools. Herding is at least twice as old as agriculture, and animal domestication is at least twice as old as plant domestication. Long before agriculture, herders dominated the natural grasslands of Africa and Eurasia. They would use fire to expand and manage grasslands. Modern cattle, sheep, and goats were domesticated by herders, while pigs and poultry were domesticated later by sedentary farmers. Dogs were domesticated long before the start of herding, used for hunting and as watchdogs. Domestication of the horse was much later, probably by herders in steppes of Central Asia. The horse was useful for controlling cattle, in war, and later was lined to the wheel, war chariots, carts and carriages, and ploughs and harrows. Cats were domesticated for control of rodents attracted to stored food or poultry. In the New World, there were few animals domesticated, but include dogs, turkeys, guinea pigs in Meso-America, and the llama and its relatives in South America. A recent example is domestication of special rats and mice for scientific and medical research, and a few species used for their fur, like mink and chinchilla.
The Domestication of Plants - domestication of plants began slowly around ten thousand years ago. Hunter-gatherers discovered that food plants flourished when they didn’t have to compete with other undesirable plants. Thus weeding was the first step in crop cultivation. Later, people realized sowing seeds could increase food supplies, and eventually they discovered they could choose which seeds to sow, to influence yields and quality. This dawn of agriculture also signified the first civilizations. After cultivation and sowing, early farmers developed techniques for tilling, manuring, irrigation, crop rotation, harvesting, threshing, and storing. The bottle gourd, a member of the cucumber family, is the only plant species domesticated in both the New and Old Worlds. It evolved in Africa and the wild fruit survived floating across the Atlantic. The fruit was used as a container before the discovery of pottery. Prior to pottery, the only means of carrying, fermenting, and storing was in animal horns and skins, sea shells, coconut shells, water-tight baskets, carved wooden bowls, and bottle gourds. In South America they had calabashes, which along with bottle gourds may represent some of the oldest plant domestications, pre-dating pottery. There were likely older uses, but remains don’t often survive. Oldest remains are in Egypt 3500 BCE, and Mexico 7000-5500 BCE. Cotton and yams were also domesticated in both Old and New Worlds, but they were different species in each hemisphere. With plant domestication came more food, better quality food, and a huge increase in carrying capacity, possibly the biggest in ancient history.
Domestication of Micro-Organisms - Micro-organisms have been unknowingly used since the first fermentation of beer and wine, bread leavening, and cheese and yoghurt making. But it’s doubtful these were domesticated or genetically changed by artificial selection. Penicillium is an example of a fungus used in cheese making and also later used for antibiotics.
Adverse Domestication - Domestication can also have negative effects, like the unconscious domestication of pests. Agricultural weeds developed mostly in the Old World. Some weeds like thistles, buttercups, dandelions, and plantains, could survive mowing and became a nuisance in hay fields and pastures. Others survived because their seeds were difficult to separate from crop seeds, and would be sown with the crop seeds. Poppies in wheat fields is and example. If agriculture were to stop, many weed populations would crash and would revert to their pre-agricultural forms. Our ancestors inadvertently domesticated many unwanted plant species into direct competitors. Farmers have been battling weeds and lower yields for millennia, representing incalculable labor costs, and has led to the rise of modern herbicides. The New World had less weeds partly because crop husbandry is younger and less widespread there, and the plough never developed there. When Europeans introduced their crops to the New World, their weeds dominated. Most of the worst weeds in the Americas, Australia, New Zealand, and temperate Africa originated in Europe. There are also very few New World weeds in the Old World. Mexican prickly pear in Australia is an example of one exception. Rats, mice, cockroaches, are also indirect, adverse domestication. Clothes moths are very rare in the wild because their larvae depend on discarded tufts of wool of wild sheep. Once wool cloth became common, moth populations exploded in the new artificial environment.
Unconscious Extermination - Humans are generally unable to intentionally exterminate other species entirely, and has only been done with smallpox. But we have failed with many others like malaria, houseflies, dog fleas, and rose aphids. But there are many unintentional extinctions caused by humans. Over-hunting examples are giant sheep, Irish Elk (really a moose), and other large herbivores. The Clovis people in North America thrived for a thousand years using stone spear points to hunt large animals. Their disappearance coincides with the extinction of around thirty species of large mammals in North America, including the mastodon, mammoth, giant sloth, sabre-toothed tiger, and many species of camel. Kangaroos, large, flightless birds, and wombats disappeared from Australia as soon as humans arrived there. More recent examples are Moa birds of New Zealand and carrier pigeons of North America. Plant gatherers also gathered species to extinction. Often a cultivated form would survive while its wild relative would be gathered to extinction. As wild gathered species become rare, it will be searched out all the more eagerly, until none is left. Wild crop progenitors likely gathered to extinction include chilies, peanuts, garlic, ginger, and tea. Despite over gathering, hunter-gatherers were not uncaring of their environment, and some wild crops were protected and only over-gathered under threat of famine. Some carnivores were also hunted to extinction, like North American sabre toothed tigers, Greek mountain lions, and European wild boars. In the big picture, there has been a trajectory of huge destruction of wild ecosystems for agriculture, and more recently by chemical pollution; these are the consequences of the over-population problem and the world food problem. Although these problems seem overwhelming, actually there has been a lot of progress because we are now finally aware of their importance. There is hope that we are on a new trajectory of awareness and adjustment.
Ecological Chaos - Beyond extinctions, humans have also caused ecological chaos by transferring species around the world. Rabbits, prickly pear cactus, killer bees, Colorado potato beetles are examples. Single species extinctions can also trigger other chaos and disruptions to the food chain. Wooly mammoth and American buffalo are examples. Buffalo may have been almost extinct when the Clovis culture ended, but then rebounded, and numbered around sixty million by European arrival to the Great Plains, and were then hunted almost to extinction. It’s possible the natural grasslands of North America are not natural at all. Over-grazing by herders caused some of the worst chaos. Some areas like the Sahara, Kalahari, and Gobi were fragile grassland ecosystems that were ruined by over-grazing and once soil blew away, damage was irreversible. To an extent extinction is normal, but there have been historical massive extinctions, like the great Permian extinction when ninety percent of all species disappeared, and the extinction of the dinosaurs. Unfortunately current extinctions are not normal.
A Brief History of Plant Breeding - This section is a bit longer and especially interesting, so I’ve broken down some key points.
Modern plant breeders have four main objectives. Improve yield, quality, agronomic suitability, and resistance to pests and disease. In general they have been successful in the first three, but much less successful in breeding resistance to pests and disease. This situation is covered in Raoul’s other book, Return to Resistance, but basics are reiterated here.
Most plant breeders tend to belong firmly to only one of two schools of thought, “pedigree breeders” or “population breeders”. Pedigree breeders love Mendel’s laws of inheritance, and like to work with single-gene characters. These characters are present or absent, with no intermediates. Population breeders like to work with many-gene characters, which are continuously variable between a minimum and a maximum. Pedigree breeders have dominated since Mendel’s popularity around 1900. Their perspective was strengthened by molecular biology and genetic engineering in the twentieth century.
There are two kinds of resistance to crop pests and diseases (parasites), and their inheritance is controlled by singe-genes and many genes respectively. Single-gene resistances are called “vertical resistance” and many-gene resistances are called “horizontal resistance”.
Vertical resistance has some considerable advantages, which are part of its popularity. It is scientifically elegant and easy to observe and to manipulate in a breeding program. It also normally confers a “complete protection” against a parasite, across a wide area of cultivation. Which made it favorable in green revolution production of wheat and rice, in which single cultivars produced by large central breeding institutes can be planted over a large areas. These institutes are interested in multi-locational testing, to find cultivars with wide climatic adaptation potential. This philosophy has led to a major increase in the usefulness of individual cultivars, but has also led to a reduction in biodiversity.
Vertical resistance also has three grave disadvantages. 1) Breeders are dependent on finding a gene for resistance; if it cannot be found, breeding for resistance cannot even begin. 2) Vertical resistance operates against some strains of the parasite but not others, meaning resistance is temporary and can be overcome by a new strain of the parasite. This leads to a boom or bust, continuous cycle that has discouraged breeding for parasite resistance. Modern crops therefore tend to by susceptible to many crop parasites, which is why we’ve become so dependent on crop protection chemicals. 3) Breeding for vertical resistance tends to disrupt horizontal resistance. For most of the twentieth century we have been losing many-gene resistances.
Horizontal resistance is durable, and occurs in every plant, against every parasite of that plant. But it requires different methods, which have made it unpopular. Many stubbornly refuse to use or even investigate it. Raoul believes “horizontal resistance offers the only real hope we have of reducing, or possibly even eliminating, the use of pesticide chemicals in our crops.
Raoul takes shots at the “king” of vertical resistance, E.C. Stackman of University of Minnesota, teacher of Norman Borlaug. Stakman worked on vertical resistance to stem rust in wheat. Raoul argues Stakman was scientifically correct, but misunderstood vertical resistance and neglected the significance of horizontal resistance. He argues that wheat scientists continue to be the bastion of vertical resistance to this day, and attract the lion’s share of research funds, but result in unjustifiable pollution of the environment by pumping billions of dollars of pesticide chemicals onto our crops each year. He says we could probably avoid all pesticide use by proper utilization of horizontal resistance. Molecular biologists also oppose horizontal resistance because they necessarily work with single genes and are dependent on continually engineering resistance cultivars with temporary resistance.
The Quality of the Environment - Raoul refutes the notion that the rise of civilization depended on the quality of the people concerned. Environmental factors largely determine where civilization developed, and in particular, the presence of wild plants suitable for domestication stands out as the most important factor.
Staples - Staples are defined as crops important for nutrition of people. Raoul distinguishes between minor and major staples. Minor staples support a primitive system of agriculture, and enable village-level civilizations to develop, but still require most of people’s time be dedicated to food production. A major staple is agriculturally productive enough to liberate a significant number of people from food procurement, to allow for the growth of cities, the rise of arts, sciences, industry, trade, and other cultural improvements. He proposes eight crucial properties of major staples: being easily cultivated, producing a new harvest each season, being very reliable across seasons, being highly productive in food per acre, providing good return per person-hour of labour, being very nutritious, being easily cooke, and producing storable food.
From the several hundred thousand plant species, only three crops worldwide have become major staples. All are grass family, wheat, rice, and maize. Raoul says without exception all great civilizations had one of these and any area that had none of them failed to produce a civilization. He reiterates that the rise of agriculture in an improved global climate ten thousand years ago was the only solution to increase the human carrying capacity of the world’s existing environment.
Ecotypes - Raoul spends some time defending his position that the rise of civilizations are entirely dependent on the presence of major staple crops in an environment, and not at all dependent on the quality of people inhabiting an environment. He argues that human races are simply different “ecotypes”. Ecotypes are the differences between a species that occur from differences in selection pressures in different areas. For example, a mountain top plant will shift to short and stout while a plant at the bottom of the mountain will become tall and lush. Another example is moths in Britain that camouflage on tree trunks, but developed a new ecotype to blend into soot-covered cities after the industrial revolution. Ecotypes are micro-evolution and not macro-evolution, meaning that these changes are faster, reversible, and don’t lead to changes in genetic code or create new species, but instead rearrange material.
Domestication is a form of artificial micro-evolution. In all of these cases the characteristics can shift back and forth. Human race or ecotype is just variation in visible characteristics and is basically unimportant because all humans are still one species that can reproduce without problems, and can all learn any culture from birth. When we look at the rise of civilizations, they all depended on wheat, rice, or maize, and had no connection with race. Some other peoples domesticated minor staples like sorghum, potatoes, and taro, and came near supporting cities, and these also occurred across the world and transcend race. Similar with herding cultures.
Agriculture - Agriculture was the technical breakthrough to massively increase human carrying capacity, and also allowed for specialization among people as time was freed up from food procurement. Arts and sciences, teaching, medicine, law, trade, building, manufacturing, religion, government, and even war depended on the free time generated from efficient food production. Raoul argues that it’s a common misconception that hunter-gatherers had more leisure and a better quality of life than agriculturalists. This is only the case if we compare hunter-gatherers to civilized farm laborers, who are underpaid and have to work long and hard. Most civilized people are freed from hard labor. Also agriculturalists have all of the benefits from civilized knowledge such as permanent houses, education, medicine, etc. Agriculture is clearly much more productive than the wild ecosystem. Actually this underlies the concept of the “agro-ecosystem”, where farmers encourage valuable biological activity and discourages harmful biological activity.
Raoul outlines two kinds of developments in agriculture that have increased productivity and carrying capacity. One is technical/technological like plowing, irrigation, mechanization, plant breeding, natural and artificial fertilizers, and has led to a tenfold increase in yields in the last hundred years. The second is the redistribution of crop species around the world. Since the Austronesian migrations and subsequent European explorations, most crops farmers grow are of exotic origin. Examples are “Irish” potatoes, “American” wheat, corn, and soy, “Kentucky” blue grass. The only crops that originated in the US are sunflowers and Jerusalem artichokes. More examples are South American sweet potatoes in the South Pacific, Central American beans and maize in Africa, coffee from Africa, Malaysian rubber from Brazil, sugarcane from New Guinea, tomatoes and pineapples from South America, apples from Iran, grapes from Central Asia, ginger and black pepper from India, red peppers from Mexico. He says nothing of importance originated in Britain or Canada. North/south distribution of plants is governed by climate, with plants not normally thriving across tropical-temperate divides. East-west distribution is governed by time and space separation by oceans.
The Dates of Agriculture - Domestication of major staple crops happened fairly simultaneously all over the world. Total evolutionary history is three and a half billion years, total human history is about two million years; major staple crop domestication and the rise of civilizations occurred with a few centuries. Local populations reached their limits around 10,000 to 5,000 BCE, which also corresponds with the end of the last ice age and improved climate. The world became warmer wetter, and more covered in plants and complex ecosystems. Humans dependent on the improved climate and also the development of agriculture to continue increasing carrying capacity.
Ease of Cultivation - Staple crops only become staples by being relatively easy to cultivate. Potatoes wouldn’t be useful if they grew four feet underground, wheat wouldn’t be useful if grains had to be picked up from the ground. One exception is rice, which is more challenging to cultivate, but has exceptional productivity.
Productivity - Productivity means both amount produced per area of land, but also frequency of production. Major staples must produce a harvest at least once per year. Rice can produce two or three harvests in a year. Ginseng takes five years, and thus could never become a staple. Tree crops produce a yearly harvest, but take years to establish. Brazil nuts require eighty years before producing a harvest.
Reliability - If a crop is too susceptible to failure, it cannot become a major staple. Too much sensitivity to drought, frost, or pests and disease will undermine the productivity of a crop. Raoul points out that it was actually in the twentieth century that durable resistance to pests and disease was lost, because of the poor science of the ag industry; we’ve actually reintroduced instability into previously stable crops like wheat, beans, rice, and potatoes.
Return for Labour - Return for labour differs from productivity in that it involves labor hours of work to procured a unit of food, rather than unit produced per unit of land or time. If a crop doesn’t produce enough food to justify the labor required, it cannot become a staple. A crop must produce enough food for many people from each hour of labor required.
Adjuncts of Staples - In regions with major staple crops, adjunct food crops were also domesticated but were not capable of supporting civilization on their own. The most important of these were plants that produce protein, legumes/pulses. In wheat areas this was peas, fava beans, and lentils; in maize areas this was haricot and other Phaseolus beans. In rice areas they were soybeans and other species. Other adjuncts included barley, millets, sorghum, and many fruits and vegetables. Some other crops had non-food value, such as for fiber, oil, drugs, beverages, and perfumes.
Minor Staples and Minor Civilizations - A few minor staples were domesticated that permitted modest civilizations to develop, which usually never grew beyond large villages and had limited culture and development. Examples are potatoes that could be frozen, dried, and stored. High-altitude potato people ruled the Incan empire despite low-altitude corn people having more advanced civilization. Ruins of an ancient civilization in Zimbabwe suggest people there depended on sorghum and millets as their staples, and their ruins pre-date introduction of maize, sweet potatoes, and cassava.
Areas Lacking the Major Staples - Areas without wheat, rice, or maize failed to develop a major civilization. Deprived zones include temperate North and South America, sub-Saharan Africa, and Australasia.
Temperate North America - Pilgrims arriving in North America met mostly indigenous who were mostly hunter-gatherers. A few had primitive agriculture with crops and techniques that had come from the South relatively recently. These were not established enough to support a civilization yet. As one traveled south, importance of agriculture based on maize increased, as did the degree of civilization, although these civilizations had not survived modern climate changes and decimation from Spanish-introduced diseases.
Temperate South America - No crops originated in temperate South America, and no agriculture or civilization developed there either. Although the potato is in a sense a temperate crop because it was domesticated in the cool, high altitudes of the Andes. Although the potato would be come a hugely important crop in temperate countries, this didn’t happen until quite recently.
Africa South of the Sahara - In sub-Saharan Africa, hunter-gatherers were replaced by herders who were themselves later replaced by agriculturalists. These farmers lacked the major staples, but grew millets, sorghum, yams, and bananas. It was not until the Portuguese introduction of maize, beans, sweet potatoes, and cassava that a really productive food supply became available. These crop introductions transformed the carrying capacity of the African environment, but was less than five centuries ago, which is not enough time to develop civilization, especially when assailed by technically advanced foreigners and slave traders.
Australia - Australia also had no indigenous plants suitable for domestication. European arrival encountered hunter-gatherers, considered them primitive and genetically inferior, but themselves failed to domesticated any native plants. Raoul notes that hunter-gatherers often exhibit amazing artistic abilities, such as aboriginal Australians who continue an unbroken cultural tradition of beautiful rock painting at least 20,000 years old.
Papua New Guinea - Some of the oldest agriculture in the world was in Papua New Guinea, 9000 years ago, but these people did not have any suitable wild plants to domesticate into a major staple food crop. Taro was a traditional crop that requires a lot of labor for relatively little food. The Portuguese introduced maize, beans, cassava, sweet potatoes, and pigs.
Chapter 4 - Civilisation
Civilization Defined - Civilization may be defined as the growth of cities, and everything that contribute and emanates from this growth, such as various artisan, industrial, artistic, professional, and intellectual skills. An essential feature is only a small portion of a large population need be occupied in food production, creating spare time for other activities and specialization. Law and order and government become essential in order for artisans and professionals to develop their spheres of activity.
Population Density - Growth of cities depend on a large population, which is only possible with staple food crops.
Hierarchies - Dominance hierarchies emerge in increases population densities. They are common in other social species, but have largely disappeared with humans and have been replaced by pair bonding or love. With love and good pair bonds, individuals cooperate rather than compete. This altruism predominates in small bands of hunter-gatherers. When populations become large, love is no longer effective because bonding is dependent on individual interactions. Cooperation becomes replaced by competition or confrontation, and can lead to crimes like theft, murder, and war. In order to cope with this problem, humans have returned to a more primitive, less pleasant system of social control based on dominance hierarchies. The essential feature of this hierarchy is domination of lower by higher. Also the higher the rank, the fewer the people in it. One king, many serfs, and serfs are often miserable. Raoul argues this is a natural consequence of major increases in carrying capacity, and that all early cities and states were characterized by despotism and tyranny. The trend of democracy represents a relatively recent attempt to transcend dominance hierarchies.
Religion - Raoul argues religion is another form of social control. A common theme of religion is persuading people to behave well by both threats of punishments and promises of reward, often without verification because these consequences occur after death. More oppressive tactics included using shame, guilt and fear.
The Effects of Living in a Fixed Location - Hunter-gatherers must be constantly nomadic and on the move in order to survive. Herders also must move daily and seasonally. Crop cultivators must stay near their crops in order to survive. Agriculture can lead to population increases due to more food supply, but also by decreasing mortality rate overall. Mothers can care for children better in a permanent home, mortality of children and the sick is reduced, farming is less dangerous than hunting. More food and increased life expectancy and mutually reinforce each other and result in population increases. Hunter-gatherers prefer lightweight baskets and pottery didn’t come into general use until agriculture due to pottery’s weight and fragility. A few groups developed pottery before agriculture, as in Japan. Living in a fixed location also allows for permanent buildings. Camp sites for hunter-gatherers became permanent villages for cultivators. Villages would tend to grow in size until entirely new phenomena of civilization would begin to appear.
Calendars - Remaining in a fixed place led to important developments in astronomy. Hunter-gatherers and herders were nomads and used a lunar calendar, which is the oldest calendar and still widely used. It’s still used in Islamic countries, in the Judaic religion, and some Christian festivals; was used in China for millenia. It’s an inaccurate calendar because the twelve lunar months is out of phase with the solar year by eleven days. This doesn’t matter much to nomads, but is vital to farmers who require accurate timing. Settled people also have to calculate how long food stores will last. Solar calendars depend on remaining in one place to measure the spot on the horizon where the sun rises or sets each day. Solar calendars were only developed by crop cultivators and it seems every major ag society succeeded in developing one. Stonehenge was only built after wheat farming had reached Britain. The Mayan calendar can measure time in millions of years.
Mathematics - All of the original civilizations independently discovered mathematics and developed it according to their needs. Math may have first developed with the study of calendars, but architecture led to the development of geometry. Ancient Mesopotamian mathematics was based on the numbers five and twelve and their product of sixty, which is where our clock system comes from. Sixty seconds to a minute, sixty minutes to an hour, twelve subdivisions of five minutes each, and twelve hours of day or night. 360 degree circle is and degrees of latitude and longitude are based on the same concept, 60x60=360. Five and twelve are also fundamental because we have five fingers of one hand, twelve months in one year. Only later did ten fingers of both hands become the basic system, which isn’t always the most functional. Computers use eight as a basic number.
Writing - History was passed down through folklore and poetry until writing was developed to create a permanent record. Writing marks the boundary between pre-history and history. We consider civilizations pre-history when there are only ruins, but part of history if we can decipher their written record. Ancient Mayan, Egyptian, and Minoans used to be pre-history but their writings have been deciphered and thus become history. Over time, literacy became common as writing was used to make public announcements, and for recording poetry and diplomacy. Eventually scholars began using writing to document their work.
Individual Ownership - With the development of permanent buildings came the concepts of individual ownership and wealth. Nomadic people have few possessions and have limited concepts of ownership. But secure houses and villages can hold many possessions and surpluses, like food, animals, tools, clothing, adornments, and cult objects. Possibly the first concepts of individual ownership of land, rather than simply communal territory.
Taxation - As cities grew, governments became more sophisticated, and taxation became needed to feed the non-producers of food. Before money, taxes could be paid as non-perishable farm produce like grain, or as corvée labor.
Corvée Labour - Corvée labor is named after the French statute labour that existed until the revolution in 1776. It’s also called involuntary labor and was usually an ancient form of taxation enforced by the military. It was normally exacted in the farming slack season, likely to keep idle hands occupied. It was very productive in creating the first monumental public works. An example is in ancient Egypt, which had strictly seasonal agriculture based on flooding of the Nile. There was little work for farmers in the off season, so they were forced into laboring to build the pyramids, palaces, tombs, and temples. There were similar patterns of corvée labor in ancient China, Mesopotamia, Central America, and also the Catholic Church in the New World. Cholula, Mexico has the largest ancient pyramids as well as 365 churches. Stonehenge was probably build by corvée labor, probably took 1500 workers ten years to transport the stones, likely done in the farming off-season. Similar involuntary labor would happen in times of war, through conscription of soldiers. Raoul argues that authoritarianism developed in every agricultural society. This reinforces the idea that ecotype or race is unimportant. Authoritarianism and despotism are connected with dominance hierarchies that come about in high population densities.
Hydraulic Cultures - “Hydraulic cultures” are civilizations that depend on crop irrigation from major rivers. Civilizations on the Tigris-Euphrates, Nile, Indus Valley, Yellow and Yangtze all developed farming with high crop yields and high population densities, and the first large-scale urbanization. They often had extreme authoritarianism because of the drive to manage irrigation and corvée labor as a single authority. Original irrigation was dependent on natural flow of water to move water upward, usually a natural river flood plain. Over time, simple bucket lifting mechanisms came about, and much later windmills to pump water.
Rainfed Cultures - Hydraulic cultures occupied a very small total area of the world, while rainfed agriculture was immense. Over time rainfed cultures became far more numerous and important than hydraulic cultures.
The Poverty Cycle - As carrying capacity of the environment was increased by agriculture, populations always grew to the new limits. Social hierarchy involved wealth and control for some, and poverty for many. Human population has nearly always exceeded carrying capacity, and poverty-stricken peasantry has been the general rule through all of recorded history. Food surplus always led to temporary declines in poverty, but the surplus also led to another population increase, causing more poverty. Raoul argues the only solution to the poverty cycle is to control the size of our total population.
Civilization Collapse - There is a historical pattern of civilization collapse, as population increases come with cultural developments, but also lead to inevitable excessive population growth. Raoul argues the rise and fall of civilizations depends mostly on whether a population exceeded their carrying capacity or not, more than the importance of good or bad rulers, war and peace, invasions and pestilence.
Thomas Malthus - Malthus (“an obnoxious Englishman”) wrote an unusually influential pamphlet at the end of the eighteenth century. He argues that human population would always grow more quickly than food supply, and therefore the majority of people would always have to live at bare subsistence level. Raoul argues Malthus was wrong because he did not recognize the possibility of birth control and stabilization of population growth. But these ideas have been long used to justify poverty and excuse wealth. Malthus didn’t understand ecology, or how intelligent beings can overcome the three brutal laws. Raoul argues the final nail in the Malthusian coffin will come soon when we finally stabilize our population at the optimum size.
Social Darwinism - Darwin was influenced by Malthus, and others mistakenly applied his theory of evolution to the growth of human culture and living conditions. “Social Darwinism” argued that within human society, the fittest survive the struggle for existence, and the weak must lose out. This was used to justify class structure and vast wealth, arguing that the possession of wealth was the result of a superior “fitness”. This argument was used by extreme right capitalists explaining their success and as an argument used against attempt to improve the lot of the poor. We now know that differences in ability depend mostly on differences in education and opportunity for education, and home/family culture. Social Darwinism postulates that ability depends purely on genres, while we now know it’s at least as much environmental. It’s also wrong in equating laws of the jungle applying to laws within human society. Society depends on cooperation and altruism, not the struggle for existence or survival of the fittest. Raoul argues competition can be either destructive or constructive. Sports and commerce can be healthy in a human society. Raoul explains that social Darwinism eventually led to the rise of Hitler and the holocaust, but he now considers the concept almost gone except in the minds of a few fanatics.
Chapter 5 - Human Health - Development of civilization depends primarily on the availability of plants suitable for domestication, but of secondary importance is human health. Different environments are more benign than others, but also range in distribution of disease pathogens.
Our Tropical Center of Origin - Tropical Africa is the center of human origin. Our human parasites also evolved with us in this tropical climate. When people migrated to cool, temperate conditions, many of those parasites died out. People who remained in Africa were disadvantaged by having to battle many debilitating diseases like malaria. These diseases impacted life expectancy, which made development of civilization less likely, apart from considerations of food supply.
Loss of Parasites - The further people migrated out of Africa, the more parasites they lost. Parasites died off in cold conditions, but also sick people died off more easily; natives of the New World were entirely free of and isolated from many diseases, including tropical African ones, also “crowd diseases” of Europe and Asia (smallpox and measles), and cattle-associated diseases (tuberculosis).
Re-Encouter Diseases - All parasites can be categorized as old encounter, new encounter, or re-encounter. Old encounter means the parasite has remained in contact with the host since first evolution, like malaria in humans, rust in wheat, and foot and mouth disease in bovines. New encounter means parasites evolved separately from their new host, in another part of the world, like Chagas disease, AIDS virus, Colorado potato beetle. Re-encounter means a parasite that was left behind, but then reunited at a later date in a new location. Re-encounter diseases are what happened when Europeans and their African slaves arrived in the New World. Another example is when Europeans first returned to tropical Africa. A plant example is tropical rust of maize in Africa. Re-encounter diseases are often particularly damaging because the host’s resistance has been lost.
Europeans and Africans in the New World - Europeans inadvertently introduced many diseases from Europe and Africa to native people in the New World. Including smallpox, measles, rubella chicken pox, mumps, whooping cough, typhoid, typhus, bubonic plague, diphtheria, tuberculosis, scarlet fever, malaria, cholera, amoebic dysentery, leprosy, and yellow fever. These were old encounter diseases for Europeans and Africans, but re-encounter diseases for New World peoples, who had no antibodies or resistance. Minority Europeans had little need to conquer by military means, as diseases did the work for them. Areas with the lowest indigenous population densities suffered the most, in the temperate areas of North and South America, which were mainly hunter-gatherers. Many of these tribes went extinct, and more are dying out. However in agricultural areas of the New World, indigenous population densities were much higher, and survival rates were higher. In Mexico there are six million people who still speak the Aztec language, and one million who speak the languages of the Mayas. Most people there now speak European languages, but they are still mainly of indigenous and especially “agricultural indigenous” descent.
Europeans in Tropical Africa - When Europeans first travelled to tropical Africa, the opposite situation happened, where the invaders were devastated by re-encounter diseases, which killed them off. To this day, Africa is populated by Africans, not Europeans.
Disease Vulnerability - “Disease vulnerability” means that a population of people, plants, or animals is susceptible to a foreign parasite which is absent from the area in question. Meaning the vulnerability may be invisible or unsuspected. New World Amerindians were highly vulnerable to European and African diseases. Similarly there are many domesticated plants and animals vulnerable to foreign pests that are absent in their localities. This is one of the tasks for agriculturalists, to identify vulnerabilities to crops or animals, and develop resistant varieties or vaccines, in advance of foreign parasites arriving. Raoul gives the interesting example of smallpox. The disease has been eradicated worldwide, so children are no longer vaccinated. But within just one generation, the entire human population will become susceptible to smallpox. This is a human-made disease vulnerability. For this reason there are still collections of the smallpox organism, to use to manufacture a vaccine should the need arise. But this represents the scary possibility of an accidental or nefarious escape of the pathogen back into humans.
People-Importing and People-Exporting Countries - Raoul argues that the devastation from disease re-encounters led huge areas of land unoccupied, available for the first people who claimed it. Europe, Asia, and Africa remained mainly people-exporting areas, and New World and Australia became people-important areas. Populations with both agriculture and disease resistance expanded, those with ag and little resistance contracted, those with neither usually went extinct. Crowded populations tended to move into the territory of diminishing populations. Commerce, warfare, and slavery may have been factors in global patterns, but these were not as impactful as the underlying factors of population growth and decline resulting from the agriculture and disease.