Neolithic Revolution
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The Neolithic Revolution, also known as the First Agricultural Revolution, was the wide-scale transition of many human cultures during the Neolithic period in Afro-Eurasia from a lifestyle of hunting and gathering to one of agriculture and settlement, making an increasingly large population possible.[1] These settled communities permitted humans to observe and experiment with plants, learning how they grew and developed.[2] This new knowledge led to the domestication of plants into crops.[2][3]
Archaeological data indicate that the domestication of various types of plants and animals happened in separate locations worldwide, starting in the geological epoch of the Holocene 11,700 years ago, after the end of the last Ice Age.[4] It was humankind's first historically verifiable transition to agriculture. The Neolithic Revolution greatly narrowed the diversity of foods available, resulting in a decrease in the quality of human nutrition compared with that obtained previously from hunting and foraging.[5][6][7] However, because food production became more efficient, it released humans to invest their efforts in other activities and was thus "ultimately necessary to the rise of modern civilization by creating the foundation for the later process of industrialization and sustained economic growth".[8]
The Neolithic Revolution involved much more than the adoption of a limited set of food-producing techniques. During the next millennia, it transformed the small and mobile groups of hunter-gatherers that had hitherto dominated human prehistory into sedentary (non-nomadic) societies based in built-up villages and towns. These societies radically modified their natural environment by means of specialized food-crop cultivation, with activities such as irrigation and deforestation which allowed the production of surplus food. Other developments that are found very widely during this era are the domestication of animals, pottery, polished stone tools, and rectangular houses. In many regions, the adoption of agriculture by prehistoric societies caused episodes of rapid population growth, a phenomenon known as the Neolithic demographic transition.
These developments, sometimes called the Neolithic package,[9] provided the basis for centralized administrations and political structures, hierarchical ideologies,[10] depersonalized systems of knowledge (e.g. writing), densely populated settlements, specialization and division of labour, more trade, the development of non-portable art and architecture, and greater property ownership.[11] The earliest known civilization developed in Sumer in southern Mesopotamia (c. 6,500 BP); its emergence also heralded the beginning of the Bronze Age.[12]
The relationship of the aforementioned Neolithic characteristics to the onset of agriculture, their sequence of emergence, and their empirical relation to each other at various Neolithic sites remains the subject of academic debate. It is usually understood to vary from place to place, rather than being the outcome of universal laws of social evolution.[13][14]
Background
[edit]Prehistoric hunter-gatherers had different subsistence requirements and lifestyles from agriculturalists. Hunter-gatherers were often highly mobile and migratory, living in temporary shelters and in small tribal groups, and having limited contact with outsiders. Their diet was well-balanced[citation needed] though heavily dependent on what the environment could provide each season. In contrast, because the surplus and plannable supply of food provided by agriculture made it possible to support larger population groups, agriculturalists lived in more permanent dwellings in more densely populated settlements than what could be supported by a hunter-gatherer lifestyle. The agricultural communities' seasonal need to plan and coordinate resource and manpower encouraged division of labour, which gradually led to specialization of labourers and complex societies. The subsequent development of trading networks to exchange surplus commodities and services brought agriculturalists into contact with outside groups, which promoted cultural exchanges that led to the rise of civilizations and technological evolutions.[15][full citation needed]
However, higher population and food abundance did not necessarily correlate with improved health. Reliance on a very limited variety of staple crops can adversely affect health even while making it possible to feed more people. As an example from the Americas, maize is deficient in certain essential amino acids (lysine and tryptophan) and is a poor source of iron. The phytic acid it contains may inhibit nutrient absorption. Other factors that likely affected the health of early agriculturalists and their domesticated livestock would have been increased numbers of parasites and disease-bearing pests associated with human waste and contaminated food and water supplies. Fertilizers and irrigation may have increased crop yields but also would have promoted proliferation of insects and bacteria in the local environment while grain storage attracted additional insects and rodents.[15]
Agricultural transition
[edit]
The term 'neolithic revolution' was invented by V. Gordon Childe in his book Man Makes Himself (1936).[18][19] Childe introduced it as the first in a series of agricultural revolutions in Middle Eastern history,[20] calling it a "revolution" to denote its significance, the degree of change to communities adopting and refining agricultural practices.[20]
The beginning of this process in different regions has been dated from 10,000 to 8,000 BCE in the Fertile Crescent,[21][22] and perhaps 8000 BCE in the Kuk Early Agricultural Site of Papua New Guinea in Melanesia.[23][24] Everywhere, this transition is associated with a change from a largely nomadic hunter-gatherer way of life to a more settled, agrarian one, with the domestication of various plant and animal species – depending on the species locally available, and influenced by local culture. Archaeological research in 2003 suggests that in some regions, such as the Southeast Asian peninsula, the transition from hunter-gatherer to agriculturalist was not linear, but region-specific.[25]
Domestication
[edit]Crops
[edit]Once agriculture started gaining momentum, around 9000 BP, human activity resulted in the selective breeding of cereal grasses (beginning with emmer, einkorn and barley), and not simply of those that favoured greater caloric returns through larger seeds. Plants with traits such as small seeds or bitter taste were seen as undesirable. Plants that rapidly shed their seeds on maturity tended not to be gathered at harvest, therefore not stored and not seeded the following season; successive years of harvesting spontaneously selected for strains that retained their edible seeds longer.
Daniel Zohary identified several plant species as "pioneer crops" or Neolithic founder crops. He highlighted the importance of wheat, barley and rye, and suggested that domestication of flax, peas, chickpeas, bitter vetch and lentils came a little later. Based on analysis of the genes of domesticated plants, he preferred theories of a single, or at most a very small number of domestication events for each taxon that spread in an arc from the Levantine corridor around the Fertile Crescent and later into Europe.[26][27] Gordon Hillman and Stuart Davies carried out experiments with varieties of wild wheat to show that the process of domestication would have occurred over a relatively short period of between 20 and 200 years.[28]
Some of the pioneering attempts failed at first and crops were abandoned, sometimes to be taken up again and successfully domesticated thousands of years later: rye, tried and abandoned in Neolithic Anatolia, made its way to Europe as weed seeds and was successfully domesticated in Europe, thousands of years after the earliest agriculture.[29] Wild lentils presented a different problem: most of the wild seeds do not germinate in the first year; the first evidence of lentil domestication, breaking dormancy in their first year, appears in the early Neolithic at Jerf el Ahmar (in modern Syria), and lentils quickly spread south to the Netiv HaGdud site in the Jordan Valley.[29] The process of domestication allowed the founder crops to adapt and eventually become larger, more easily harvested, more dependable[clarification needed] in storage and more useful to the human population.
Selectively propagated figs, wild barley and wild oats were cultivated at the early Neolithic site of Gilgal I, where in 2006[30] archaeologists found caches of seeds of each in quantities too large to be accounted for even by intensive gathering, at strata datable to c. 11,000 years ago. Some of the plants tried and then abandoned during the Neolithic period in the Ancient Near East, at sites like Gilgal, were later successfully domesticated in other parts of the world.
Once early farmers perfected their agricultural techniques like irrigation (traced as far back as the 6th millennium BCE in Khuzestan[31][32]), their crops yielded surpluses that needed storage. Most hunter-gatherers could not easily store food for long due to their migratory lifestyle, whereas those with a sedentary dwelling could store their surplus grain. Eventually granaries were developed that allowed villages to store their seeds longer. So with more food, the population expanded and communities developed specialized workers and more advanced tools.
The process was not as linear as was once thought, but a more complicated effort, which was undertaken by different human populations in different regions in many different ways.
One of the world's most important crops, barley, was domesticated in the Near East around 11,000 years ago (c. 9,000 BCE).[33] Barley is a highly resilient crop, able to grow in varied and marginal environments, such as in regions of high altitude and latitude.[33] Archaeobotanical evidence shows that barley had spread throughout Eurasia by 2,000 BCE.[33] To further elucidate the routes by which barley cultivation was spread through Eurasia, genetic analysis was used to determine genetic diversity and population structure in extant barley taxa.[33] Genetic analysis shows that cultivated barley spread through Eurasia via several different routes, which were most likely separated in both time and space.[33]
Livestock
[edit]When hunter-gathering began to be replaced by sedentary food production it became more efficient to keep animals close at hand. Therefore, it became necessary to bring animals permanently to their settlements, although in many cases there was a distinction between relatively sedentary farmers and nomadic herders.[34][original research?] The animals' size, temperament, diet, mating patterns, and life span were factors in the desire and success in domesticating animals. Animals that provided milk, such as cows and goats, offered a source of protein that was renewable and therefore quite valuable. The animal's ability as a worker (for example ploughing or towing), as well as a food source, also had to be taken into account. Besides being a direct source of food, certain animals could provide leather, wool, hides, and fertilizer. Some of the earliest domesticated animals included dogs (East Asia, about 15,000 years ago),[35] sheep, goats, cows, and pigs.
West Asia was the source for many animals that could be domesticated, such as sheep, goats and pigs. This area was also the first region to domesticate the dromedary. Henri Fleisch discovered and termed the Shepherd Neolithic flint industry from the Bekaa Valley in Lebanon and suggested that it could have been used by the earliest nomadic shepherds. He dated this industry to the Epipaleolithic or Pre-Pottery Neolithic as it is evidently not Paleolithic, Mesolithic or even Pottery Neolithic.[36]