Agriculture began independently in different parts of the globe, and included a diverse range of
taxa. At least eleven separate regions of the
New World were involved as independent
centers of origin.
The development of agriculture about 12,000 years ago changed the way humans lived. They switched from nomadic hunter-gatherer lifestyles to permanent settlements and farming.
grains were collected and eaten from at least 105,000 years ago. However, domestication did not occur until much later. The earliest evidence of small-scale cultivation of edible grasses is from around 21,000 BC with the
Ohalo II people on the shores of the
Sea of Galilee. By around 9500 BC, the eight
Neolithic founder crops –
flax – were cultivated in the
Levant.Rye may have been cultivated earlier, but this claim remains controversial.Rice was domesticated in China by 6200 BC with earliest known cultivation from 5700 BC, followed by
azuki beans. Rice was also independently domesticated in West Africa and cultivated by 1000 BC.Pigs were domesticated in Mesopotamia around 11,000 years ago, followed by
Cattle were domesticated from the wild
aurochs in the areas of modern Turkey and India around 8500 BC.
Camels were domesticated late, perhaps around 3000 BC.
In South America, agriculture began as early as 9000 BC, starting with the cultivation of several species of plants that later became only minor crops. In the
Andes of South America, the
potato was domesticated between 8000 BC and 5000 BC, along with
Cassava was domesticated in the Amazon Basin no later than 7000 BC.
Maize (Zea mays) found its way to South America from
Mesoamerica, where wild
teosinte was domesticated about 7000 BC and
selectively bred to become domestic maize.
Cotton was domesticated in
Peru by 4200 BC; another species of cotton was domesticated in Mesoamerica and became by far the most important species of cotton in the textile industry in modern times. Evidence of agriculture in the
Eastern United States dates to about 3000 BCE. Several plants were cultivated, later to be replaced by the
Three Sisters cultivation of maize, squash, and beans.
Scholars have developed a number of hypotheses to explain the historical origins of agriculture. Studies of the transition from
hunter-gatherer to agricultural societies indicate an antecedent period of intensification and increasing
sedentism; examples are the
Natufian culture in the
Levant, and the Early Chinese Neolithic in China. Current models indicate that wild stands that had been harvested previously started to be planted, but were not immediately domesticated.
Localised climate change is the favoured explanation for the origins of agriculture in the Levant. When major climate change took place after the last
ice age (c. 11,000 BC), much of the earth became subject to long dry seasons. These conditions favoured
annual plants which die off in the long dry season, leaving a
tuber. An abundance of readily storable wild grains and
pulses enabled hunter-gatherers in some areas to form the first settled villages at this time.
Early people began altering communities of
fauna for their own benefit through means such as
fire-stick farming and
forest gardening very early.
grains have been collected and eaten from at least 105,000 years ago, and possibly much longer. Exact dates are hard to determine, as people collected and ate seeds before domesticating them, and plant characteristics may have changed during this period without human selection. An example is the semi-tough
rachis and larger seeds of
cereals from just after the
Younger Dryas (about 9500 BC) in the early
Holocene in the
Levant region of the
Monophyletic characteristics were attained without any human intervention, implying that apparent domestication of the cereal
rachis could have occurred quite naturally.
Agriculture began independently in different parts of the globe and included a diverse range of taxa. At least 11 separate regions of the Old and New World were involved as independent
centers of origin. Some of the earliest known domestications were of animals.
Domestic pigs had multiple centres of origin in Eurasia, including Europe, East Asia and Southwest Asia, where
wild boar were first domesticated about 10,500 years ago.Sheep were domesticated in Mesopotamia between 11,000 BC and 9000 BC.Cattle were domesticated from the wild
aurochs in the areas of modern Turkey and Pakistan around 8500 BC.Camels were domesticated relatively late, perhaps around 3000 BC.
By 8000 BC, farming was entrenched on the banks of the
Nile. About this time, agriculture was developed independently in the Far East, probably in China, with rice rather than wheat as the primary crop. Maize was domesticated from the wild grass
teosinte in southern Mexico by 6700 BC.
potato (8000 BC),
tomato,pepper (4000 BC),
squash (8000 BC) and several varieties of
bean (8000 BC onwards) were domesticated in the New World.
Bees were kept for honey in the Middle East around 7000 BC. Archaeological evidence from various sites on the
Iberian peninsula suggest the domestication of plants and animals between 6000 and 4500 BC.Céide Fields in
Ireland, consisting of extensive tracts of land enclosed by stone walls, date to 3500 BC and are the oldest known field systems in the world. The
horse was domesticated in the
Pontic steppe around 4000 BC. In
Cannabis was in use in China in Neolithic times and may have been domesticated there; it was in use both as a fibre for ropemaking and as a medicine in Ancient Egypt by about 2350 BC.
Sumerian farmers grew the cereals
wheat, starting to live in villages from about 8000 BC. Given the low rainfall of the region, agriculture relied on the
Euphrates rivers. Irrigation canals leading from the rivers permitted the growth of cereals in large enough quantities to support cities. The first ploughs appear in
pictographs from Uruk around 3000 BC; seed-ploughs that funneled seed into the ploughed furrow appear on
seals around 2300 BC. Vegetable crops included
lentils, peas, beans,
mustard. They grew fruits including
dates, grapes, apples, melons, and figs. Alongside their farming, Sumerians also caught fish and hunted
gazelle. The meat of sheep, goats, cows and poultry was eaten, mainly by the elite. Fish was preserved by drying, salting and smoking.
The civilization of
Ancient Egypt was indebted to the
Nile River and its dependable seasonal flooding. The river's predictability and the fertile soil allowed the Egyptians to build an empire on the basis of great agricultural wealth. Egyptians were among the first peoples to practice agriculture on a large scale, starting in the pre-dynastic period from the end of the Paleolithic into the Neolithic, between around 10,000 BC and 4000 BC. This was made possible with the development of basin irrigation. Their staple food crops were grains such as wheat and barley, alongside industrial crops such as
papyrus. Archaeological evidence also suggests that the spread of agriculture was facilitated by the influx of farming communities from the tropical Sahara 6,500 years ago.
Jujube was domesticated in the
Indian subcontinent by 9000 BC. Barley and wheat cultivation – along with the domestication of cattle, primarily sheep and goats – followed in
Mehrgarh culture by 8000–6000 BC. This period also saw the first domestication of the
elephant.Pastoral farming in
India included threshing, planting crops in rows – either of two or of six – and storing grain in
granaries.Cotton was cultivated by the 5th–4th millennium BC. By the 5th millennium BC, agricultural communities became widespread in
Kashmir. Irrigation was developed in the
Indus Valley Civilisation by around 4500 BC. The size and prosperity of the Indus civilization grew as a result of this innovation, leading to more thoroughly planned settlements which used
sewers. Archeological evidence of an animal-drawn
plough dates back to 2500 BC in the Indus Valley Civilization.
Records from the
Qin dynasty, and
Han dynasty provide a picture of early
Chinese agriculture from the 5th century BC to 2nd century AD which included a nationwide
granary system and widespread use of
sericulture. An important early Chinese book on agriculture is the
Qimin Yaoshu of AD 535, written by Jia Sixie. Jia's writing style was straightforward and lucid relative to the elaborate and allusive writing typical of the time. Jia's book was also very long, with over one hundred thousand written
Chinese characters, and it quoted many other Chinese books that were written previously, but no longer survive. The contents of Jia's 6th century book include sections on land preparation, seeding, cultivation, orchard management, forestry, and animal husbandry. The book also includes peripherally related content covering trade and culinary uses for crops. The work and the style in which it was written proved influential on later Chinese
agronomists, such as
Wang Zhen and his groundbreaking Nong Shu of 1313.
For agricultural purposes, the Chinese had innovated the
trip hammer by the 1st century BC. Although it found other purposes, its main function to pound, decorticate, and polish grain that otherwise would have been done manually. The Chinese also began using the square-pallet
chain pump by the 1st century AD, powered by a
oxen pulling an on a system of mechanical wheels. Although the chain pump found use in
public works of providing water for urban and palatial
pipe systems, it was used largely to lift water from a lower to higher elevation in filling
farmland. By the end of the
Han dynasty in the late 2nd century,
heavy ploughs had been developed with iron ploughshares and
mouldboards. These slowly spread west, revolutionizing farming in Northern Europe by the 10th century. (
Thomas Glick, however, argues for a development of the Chinese plough as late as the 9th century, implying its spread east from similar designs known in Italy by the 7th century.)
Asian rice was domesticated 8,200–13,500 years ago in China, with a single genetic origin from the wild rice Oryza rufipogon, in the
Pearl River valley region of China. Rice cultivation then spread to South and Southeast Asia.
Greco-Roman world of
Roman agriculture was built on techniques originally pioneered by the Sumerians, transmitted to them by subsequent cultures, with a specific emphasis on the cultivation of crops for trade and export.
The Romans laid the groundwork for the
manorial economic system, involving
serfdom, which flourished in the Middle Ages. The farm sizes in
Rome can be divided into three categories. Small farms were from 18 to 88 iugera (one iugerum is equal to about 0.65 acre). Medium-sized farms were from 80 to 500 iugera (singular
iugerum). Large estates (called
latifundia) were over 500 iugera.
The Romans had four systems of farm management: direct work by the owner and his family; slaves doing work under the supervision of slave managers;
tenant farming or
sharecropping in which the owner and a tenant divide up a farm's produce; and situations in which a farm was leased to a tenant.
Agricultural history took a different path from the
Old World as the Americas lacked large-seeded, easily domesticated grains (such as wheat and barley) and large domestic animals that could be used for agricultural labor. Rather than the practice which developed in the Old World of sowing a field with a single crop, pre-historic American agriculture usually consisted of cultivating many crops close to each other utilizing only hand labor. Moreover, agricultural areas in the Americas lacked the uniformity of the east–west area of
semi-arid climates in southern Europe and southwestern Asia, but instead had a north–south pattern with a variety of different climatic zones in close proximity to each other. This fostered the domestication of many different plants.
At the time of first contact between the Europeans and the Americans, the Europeans practiced "extensive agriculture, based on the plough and draught animals," with tenants under landlords, but also forced labor or slavery, while the
Indigenous peoples of the Americas practiced "intensive agriculture, based on human labour." Europeans wanted control of land for the grazing of their livestock and property rights for the control of production. Though they were impressed with the productivity of traditional farming techniques, they saw no connection to their system and were dismissive of Native American practices as "gardening" rather than a commercializable enterprise. Due to several thousand years of selective breeding,
maize, the hemisphere's most important crop, was more productive than Old World grain crops. Maize produced two and one-half times more calories per acre than wheat and barley.
The earliest known areas of possible agriculture in the Americas dating to about 9000 BC are in
Colombia, near present-day
Pereira, and by the
Las Vegas culture in
Ecuador on the
Santa Elena peninsula. The plants cultivated (or manipulated by humans) were
lerén (Calathea allouia),
arrowroot (Maranta arundinacea),
squash (Cucurbita species), and
bottle gourd (Lagenaria siceraria). All are plants of humid climates and their existence at this time on the semi-arid Santa Elena peninsula may be evidence that they were transplanted there from more humid environments. In another study, this area of South America was identified as one of the four oldest places of origin for agriculture, along with the Fertile Crescent, China, and Mesoamerica, dated between 6200 BC and 10000 BC. (To facilitate comprehension by readers,
Radiocarbon calibrated BP dates in the above sources have been converted to BC.)
In Mesoamerica, wild
teosinte was transformed through human selection into the ancestor of modern maize, about 7,000 BC. It gradually spread across North America and to South America and was the most important crop of Native Americans at the time of European exploration. Other Mesoamerican crops include hundreds of varieties of locally domesticated
cocoa, also domesticated in the region, was a major crop. The
turkey, one of the most important poultry birds, was probably domesticated in Mexico or the U.S. Southwest.
Aztecs were active farmers and had an agriculturally focused economy. The land around
Lake Texcoco was fertile, but not large enough to produce the amount of food needed for the population of their expanding empire. The Aztecs developed irrigation systems, formed
terraced hillsides, fertilized their soil, and developed
chinampas or artificial islands, also known as "floating gardens". The
Mayas between 400 BC to 900 AD used extensive canal and raised field systems to farm swampland on the
Several species of
coffee were also domesticated throughout Sub-Saharan Africa, with Coffea arabica originating in
Ethiopia and serving as the main production of modern-day coffee since the late 15th century.
In two regions of Central Australia, the central west coast and eastern central Australia, forms of agriculture were practiced. People living in permanent settlements of over 200 residents sowed or planted on a large scale and stored the harvested food. The Nhanda and Amangu of the central west coast grew yams (Dioscorea hastifolia), while various groups in eastern central Australia (the Corners Region) planted and harvested bush onions (yaua – Cyperus bulbosus), native millet (cooly, tindil – Panicum decompositum) and a
sporocarp, ngardu (Marsilea drummondii).: 281–304 
Indigenous Australians used systematic burning,
fire-stick farming, to enhance natural productivity. In the 1970s and 1980s archaeological research in south west Victoria established that the
Gunditjmara and other groups had developed sophisticated eel farming and fish trapping systems over a period of nearly 5,000 years. The archaeologist
Harry Lourandos suggested in the 1980s that there was evidence of 'intensification' in progress across Australia, a process that appeared to have continued through the preceding 5,000 years. These concepts led the historian
Bill Gammage to argue that in effect the whole continent was a managed landscape.
Torres Strait Islanders are now known to have planted
New Guinea, archaeological evidence suggests that agriculture independently emerged around 7,000 years ago with the domestication of crops such as bananas and
taro. Pigs and chickens were imported to New Guinea, which were later innovated by other Pacific Island nations, such as those in
Middle Ages saw further improvements in agriculture.
Monasteries spread throughout
Europe and became important centers for the collection of knowledge related to agriculture and forestry. The
manorial system allowed large landowners to control their land and its laborers, in the form of
serfs. During the medieval period, the
Arab world was critical in the exchange of crops and technology between the European, Asia and African continents. Besides transporting numerous crops, they introduced the concept of summer irrigation to Europe and developed the beginnings of the
plantation system of
sugarcane growing through the use of slaves for intensive cultivation.
By AD 900, developments in
iron smelting allowed for increased production in Europe, leading to developments in the production of agricultural implements such as
hand tools and
horse shoes. The
carruca heavy plough improved on the earlier
scratch plough, with the adoption of the Chinese
mouldboard plough to turn over the heavy, wet soils of northern Europe. This led to the clearing of northern European forests and an increase in agricultural production, which in turn led to an increase in population. At the same time, some farmers in Europe moved from a two field
crop rotation to a three-field crop rotation in which one field of three was left fallow every year. This resulted in increased productivity and nutrition, as the change in rotations permitted
nitrogen-fixinglegumes such as peas, lentils and beans. Improved
horse harnesses and the
whippletree further improved cultivation.
Watermills were introduced by the Romans, but were improved throughout the Middle Ages, along with
windmills, and used to grind grains into flour, to cut wood and to process flax and wool.
Crops included wheat,
rye, barley and
oats. Peas, beans, and
vetches became common from the 13th century onward as a
fodder crop for animals and also for their
nitrogen-fixation fertilizing properties. Crop yields peaked in the 13th century, and stayed more or less steady until the 18th century. Though the limitations of medieval farming were once thought to have provided a ceiling for the population growth in the Middle Ages, recent studies have shown that the technology of medieval agriculture was always sufficient for the needs of the people under normal circumstances, and that it was only during exceptionally harsh times, such as the
terrible weather of 1315–17, that the needs of the population could not be met.
From the 8th century to the 14th century, the
Islamic world underwent a transformation in agricultural practice, described by the historian Andrew Watson as the
Arab agricultural revolution. This transformation was driven by a number of factors including the diffusion of many crops and plants along Muslim trade routes, the spread of more advanced farming techniques, and an agricultural-economic system which promoted increased yields and efficiency. The shift in agricultural practice changed the economy,
population distribution, vegetation cover, agricultural production, population levels,
urban growth, the distribution of the labour force, cooking, diet, and clothing across the Islamic world. Muslim traders covered much of the
Old World, and trade enabled the diffusion of many crops, plants and farming techniques across the region, as well as the adaptation of crops, plants and techniques from beyond the Islamic world. This diffusion introduced major crops to Europe by way of
Al-Andalus, along with the techniques for their cultivation and cuisine. Sugar cane, rice, and cotton were among the major crops transferred, along with
citrus and other fruit trees, nut trees, vegetables such as
chard, and the use of imported spices such as
cinnamon. Intensive irrigation,
crop rotation, and agricultural manuals were widely adopted. Irrigation, partly based on Roman technology, made use of
noria water wheels,
water mills, dams and reservoirs.
After 1492, a
global exchange of previously local crops and livestock breeds occurred. Maize, potatoes,
sweet potatoes and
manioc were the key crops that spread from the New World to the Old, while varieties of wheat, barley, rice and
turnips traveled from the Old World to the New. There had been few livestock species in the New World, with horses, cattle, sheep and goats being completely unknown before their arrival with Old World settlers. Crops moving in both directions across the
Atlantic Ocean caused population growth around the world and a lasting effect on many cultures in the
Early Modern period.
Maize and cassava were introduced from Brazil into Africa by Portuguese traders in the 16th century, becoming staple foods, replacing native African crops. After its introduction from South America to Spain in the late 1500s, the potato became a staple crop throughout Europe by the late 1700s. The potato allowed farmers to produce more food, and initially added variety to the European diet. The increased supply of food reduced disease, increased births and reduced mortality, causing a population boom throughout the
British Empire, the US and Europe. The introduction of the potato also brought about the first intensive use of fertilizer, in the form of
guano imported to Europe from Peru, and the first artificial pesticide, in the form of an
arsenic compound used to fight
Colorado potato beetles. Before the adoption of the potato as a major crop, the dependence on grain had caused repetitive regional and national famines when the crops failed, including 17 major famines in England between 1523 and 1623. The resulting dependence on the potato however caused the
European Potato Failure, a disastrous crop failure from
disease that resulted in widespread
famine and the death of over one million people in Ireland alone.
Between the 17th century and the mid-19th century, Britain saw a large increase in agricultural productivity and net output. New agricultural practices like
four-field crop rotation to maintain soil nutrients, and
selective breeding enabled an
unprecedented population growth to 5.7 million in 1750, freeing up a significant percentage of the workforce, and thereby helped drive the
Industrial Revolution. The productivity of wheat went up from 19 US bushels (670 L; 150 US dry gal; 150 imp gal) per
acre in 1720 to around 30 US bushels (1,100 L; 240 US dry gal; 230 imp gal) by 1840, marking a major turning point in history.
Advice on more productive techniques for farming began to appear in England in the mid-17th century, from writers such as
Walter Blith and others. The main problem in sustaining agriculture in one place for a long time was the depletion of nutrients, most importantly nitrogen levels, in the soil. To allow the soil to regenerate, productive land was often let fallow and, in some places,
crop rotation was used. The Dutch four-field rotation system was popularised by the British agriculturist
Charles Townshend in the 18th century. The system (wheat, turnips, barley and clover) opened up a fodder crop and grazing crop allowing livestock to be bred year-round. The use of clover was especially important as the legume roots replenished soil nitrates.
The mechanisation and rationalisation of agriculture was another important factor.
Robert Bakewell and
Thomas Coke introduced
selective breeding and initiated a process of inbreeding to maximise desirable traits from the mid 18th century, such as the
New Leicester sheep. Machines were invented to improve the efficiency of various agricultural operation, such as
seed drill of 1701 that mechanised seeding at the correct depth and spacing and
threshing machine of 1784. Ploughs were steadily improved, from Joseph Foljambe's
Rotherham iron plough in 1730 to
James Small's improved "Scots Plough" metal in 1763. In 1789
Ransomes, Sims & Jefferies was producing 86 plough models for different soils. Powered farm machinery began with
stationary steam engine, used to drive a threshing machine, in 1812. Mechanisation spread to additional farm uses throughout the 19th century. The first petrol-driven
tractor was built in America by
John Froelich in 1892.
Dan Albone constructed the first commercially successful gasoline-powered general-purpose tractor in 1901, and the 1923
International HarvesterFarmall tractor marked a major point in the replacement of draft animals (particularly horses) with machines. Since that time, self-propelled mechanical harvesters (
transplanters and other equipment have been developed, further revolutionizing agriculture. These inventions allowed farming tasks to be done with a speed and on a scale previously impossible, leading modern farms to output much greater volumes of high-quality produce per land unit.
Haber-Bosch method for synthesizing
ammonium nitrate represented a major breakthrough and allowed
crop yields to overcome previous constraints. It was first patented by German chemist
Fritz Haber. In 1910
Carl Bosch, while working for German chemical company
BASF, successfully commercialized the process and secured further patents. In the years after
World War II, the use of synthetic fertilizer increased rapidly, in sync with the increasing world population.
The number of people involved in farming in industrial countries fell radically from 24 percent of the American population to 1.5 percent in 2002. The number of farms also decreased, and their ownership became more concentrated; for example, between 1967 and 2002, one million pig farms in America consolidated into 114,000, with 80 percent of the production on factory farms. According to the
Worldwatch Institute, 74 percent of the world's poultry, 43 percent of beef, and 68 percent of eggs are produced this way.
Famines however continued to sweep the globe through the 20th century. Through the effects of climatic events, government policy, war and crop failure, millions of people died in each of at least ten famines between the 1920s and the 1990s.
The Green Revolution was a series of research, development, and
technology transfer initiatives, between the 1940s and the late 1970s. It increased agriculture production around the world, especially from the late 1960s. The initiatives, led by
Norman Borlaug and credited with saving over a billion people from starvation, involved the development of high-yielding varieties of cereal grains, expansion of irrigation infrastructure, modernization of management techniques, distribution of hybridized seeds, synthetic fertilizers, and
pesticides to farmers.
Synthetic nitrogen, along with mined
rock phosphate, pesticides and mechanization, have greatly increased crop yields in the early 20th century. Increased supply of
grains has led to cheaper livestock as well. Further, global yield increases were experienced later in the 20th century when high-yield varieties of common staple grains such as rice, wheat, and corn were introduced as a part of the Green Revolution. The Green Revolution exported the technologies (including pesticides and synthetic nitrogen) of the developed world to the developing world.
Thomas Malthus famously predicted that the Earth would not be able to support its growing population, but technologies such as the Green Revolution have allowed the world to produce a surplus of food.
Although the Green Revolution at first significantly increased rice yields in Asia, yield then levelled off. The genetic "yield potential" has increased for wheat, but the yield potential for rice has not increased since 1966, and the yield potential for maize has "barely increased in 35 years". It takes only a decade or two for herbicide-resistant weeds to emerge, and insects become resistant to insecticides within about a decade, delayed somewhat by crop rotation.
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ISBN978-0-521-24548-7. Chapter 4