However, the primary distinguishing feature between hunter-gatherers and the beginnings of modern agriculture lies in the domestication of species:. Hunter-gatherers promoted yield and changed environmental conditions.
However, the future seed bank was consistently derived from the plants that they left behind in the field, thus there were none of the selective pressures that promoted domestication.
Although there are many scholarly debates about the details, it is widely recognized that there are seven main areas in the world in which domestication of plant and animals arose:. Pause for thought Can you suggest 4 reasons why domestication arose in the seven areas listed above as opposed to elsewhere? Newly Cultivated Field - India. Photograph Courtesy of Dr. Why give up the hour work week and the fun of hunting in order to toil in the sun?
Why work harder for food that is less nutritious and a supply more capricious? Why invite famine, plague, pestilence and crowded living conditions? Why abandon the Golden Age and take up the burden? However, it did increase food production per unit area, making it easier to feed a population from the same amount of land around a settlement.
The alternative scenario suggests that man had to reach a certain level of social organization or tool-making development, with a settled mode of life, before agriculture was possible, and this stage of human development was only reached 9 - 10 years ago.
The move from shifting agriculture to domesticated agriculture was preceded and made possible by the millennia of accumulated experience of wild plants and animals, and trial-and-error experimentation. There was probably a gradual shift from collecting to cultivation with continued reliance on hunting and gathering.
Finally there was almost complete reliance on agriculture as the major source of nutrition. In some areas of the world, primitive methods are still the most effective. Photographs Courtesy of Dr. The stages of harvesting, planting and storing imposed various artificial selection pressures such as the following:.
Over time, these selection pressures produced changes in the crop and seeds that are characteristic of domesticated crops.
These changes referred to as domestication markers are most pronounced when comparisons are made between the domesticated crop and its wild relatives.
Typical domestication characteristics exhibited by modern varieties of maize left and Wheat right. Galton - identified behavioural and physiologic characteristics of animals which would make them better candidates for domestication i. Goats exhibit more pre-adaptations to domestication than pigs. List 5 advantages and 5 disadvantages to a community that may arise when communities become sedentary. The first tractors were steam-powered engines designed to haul agricultural equipment and were too expensive for most farmers.
The gasoline-powered tractor was invented in The last century has seen a host of changes in the way farming is carried out and in the way farm produce shows up on our tables. In , a trucking executive complained during a round of golf about how the summer heat was spoiling much of the food shipped by his company.
His companion, Joseph Numero, jokingly suggested refrigerating the trailers. The idea stuck, and Numero went on to start a refrigerated transport company with the help of inventor Frederick Jones. Meanwhile, the development of hybrid seed , and particularly hybrid corn, revolutionized agriculture.
Hybrids improve the results of planting, and often produce plants and fruits that are hardier and more uniform. Hybrid seeds contributed to the increased agricultural output of the second half of the 20th century. Despite these great improvements, other changes arrived with controversy.
During the past 10 years, a huge controversy has raged over the use of chemical pesticides and fertilizers on farms as well as genetically modified organisms. Growing awareness of how chemicals impact human health and the environment has led to calls for increased government regulation of the agricultural industry. The history of agriculture has played a huge role in human civilization.
A majority of the human population once worked in agriculture and even today few, if any, humans could survive without it. Agriculture Development : An article about the development of agriculture in China. Growing a Nation : A timeline of agricultural history in the United States. Although it brought tremendous gains in short-term productivity, it has also been a major contributor to soil erosion. The loss of fertile topsoil has played a role in the decline of numerous civilizations.
Farming probably involved more work than hunting and gathering, but it is thought to have provided 10 to times more calories per acre. Small settlements grew into towns, and towns grew into cities. Agriculture produced enough food that people became free to pursue interests other than worrying about what they were going to eat that day.
Hunting, gathering, and farming, however, can complement one another in ways that provide people with a more varied and abundant food supply. People still harvest aquatic plants and animals from the sea, for example, and even urban dwellers might find edible berries, greens, and mushrooms in their local park.
Depleted farmland and a changing climate set the stage for periodic famines throughout much of Europe from to Image attributed to Michael Wolgemut, Public domain. Agriculture may have made civilizations possible, but it has never been a safeguard against their collapse.
Throughout history, increases in agricultural productivity competed against population growth, resource degradation, droughts, changing climates, and other forces that periodically crippled food supplies, with the poor bearing the brunt of famine.
Like many of their modern counterparts, early farmers often worked land in ways that depleted its fertility. Technological innovations like irrigation circa BCE and the plow circa BCE brought enormous gains in productivity, but when used irresponsibly they degraded soil—the very foundation that makes agriculture possible.
By , economist Thomas Malthus warned that unchecked population growth would outpace food production, setting the stage for widespread starvation. In , economist Thomas Malthus warned that unchecked population growth would outpace food production, setting the stage for widespread starvation. Application of anhydrous ammonia synthetic nitrogen fertilizer at planting time on an Iowa farm. Synthetic fertilizers are manufactured using a technique that transforms nitrogen in the atmosphere into a form that can be applied to crops ammonia.
These chemicals have dramatically increased short-term crop yields, though not without consequences. The heavy use of synthetic fertilizers has become a hallmark of industrial agriculture. Freight train carrying grain across Washington state. Beyond synthetic fertilizers, other innovations in food production and distribution helped food supplies keep pace with population growth.
Expanded railways, shipping canals, and new machinery for storing and moving grain made it easier to transport food to where it was most needed.
From to , the global population grew from 1. Still, the sheer volume of production dwarfs that of earlier generations. What has made such unprecedented abundance possible?
Innovations in food production and distribution have thus far helped food supplies keep pace with population growth. Crops indigenous to the Americas, such as corn, sweet potatoes, and cassava, spread across the globe.
The nutrients provided by these prolific crops helped prevent malnutrition, supporting a widespread increase in population over the 18 th century. Of all the innovations in agriculture, arguably none has been more influential than synthetic fertilizers—chemicals manufactured using a technique that transforms nitrogen in the atmosphere into a form that can be applied to crops ammonia.
The following list of suggested resources is intended as a starting point for further exploration, and is not in any way comprehensive. Montgomery D. Dirt: The Erosion of Civilizations. Boston, MA: Houghton Mifflin; Kremer M. Q J Econ. Trinkaus E.
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