Dunbar's Number
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Dunbar's Number
Dunbar's number is a suggested cognitive limit to the number of people with whom one can maintain stable social relationships—relationships in which an individual knows who each person is and how each person relates to every other person. This number was first proposed in the 1990s by British anthropologist Robin Dunbar, who found a correlation between primate brain size and average social group size. By using the average human brain size and extrapolating from the results of primates, he proposed that humans can comfortably maintain 150 stable relationships. There is some evidence that brain structure predicts the number of friends one has, though causality remains to be seen. Dunbar explained it informally as "the number of people you would not feel embarrassed about joining uninvited for a drink if you happened to bump into them in a bar." Dunbar theorised that "this limit is a direct function of relative neocortex size, and that this, in turn, limits group size ..the limit ...
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Band Society
A band society, sometimes called a camp, or in older usage, a horde, is the simplest form of human society. A band generally consists of a small kin group, no larger than an extended family or clan. The general consensus of modern anthropology sees the average number of members of a social band at the simplest level of foraging societies with generally a maximum size of 30 to 50 people. Origins of usage in anthropology Band was one of a set of three terms employed by early modern ethnography to analyse aspects of hunter-gatherer foraging societies. The three were respectively 'horde,' 'band', and 'tribe'. The term 'horde', formed on the basis of a Turkish/Tatar word ''úrdú'' (meaning 'camp'), was inducted from its use in the works of J. F. McLennan by Alfred William Howitt and Lorimer Fison in the mid-1880s to describe a geographically or locally defined division within a larger tribal aggregation, the latter being defined in terms of social divisions categorized in terms of ...
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Evolutionary Psychology
Evolutionary psychology is a theoretical approach in psychology that examines cognition and behavior from a modern evolutionary perspective. It seeks to identify human psychological adaptations with regards to the ancestral problems they evolved to solve. In this framework, psychological traits and mechanisms are either functional products of natural and sexual selection, non-adaptive by-products of other adaptive traits, or noise. Adaptationist thinking about physiological mechanisms, such as the heart, lungs, and the liver, is common in evolutionary biology. Evolutionary psychologists apply the same thinking in psychology, arguing that just as the heart evolved to pump blood, and the liver evolved to detoxify poisons, there is modularity of mind in that different psychological mechanisms evolved to solve different adaptive problems. These evolutionary psychologists argue that much of human behavior is the output of psychological adaptations that evolved to solve recurrent p ...
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Language
Language is a structured system of communication. The structure of a language is its grammar and the free components are its vocabulary. Languages are the primary means by which humans communicate, and may be conveyed through a variety of methods, including spoken, sign, and written language. Many languages, including the most widely-spoken ones, have writing systems that enable sounds or signs to be recorded for later reactivation. Human language is highly variable between cultures and across time. Human languages have the properties of productivity and displacement, and rely on social convention and learning. Estimates of the number of human languages in the world vary between and . Precise estimates depend on an arbitrary distinction (dichotomy) established between languages and dialects. Natural languages are spoken, signed, or both; however, any language can be encoded into secondary media using auditory, visual, or tactile stimuli – for example, writing, whi ...
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Grooming, Gossip, And The Evolution Of Language
''Grooming, Gossip and the Evolution of Language'' is a 1996 book by the anthropologist Robin Dunbar, in which the author argues that language evolved from social grooming. He further suggests that a stage of this evolution was the telling of gossip, an argument supported by the observation that language is adapted for storytelling. Thesis Dunbar argues that gossip does for group-living humans what manual grooming does for other primates—it allows individuals to service their relationships and thus maintain their alliances on the basis of the principle: ''if you scratch my back, I'll scratch yours.'' Dunbar argues that as humans began living in increasingly larger social groups, the task of manually grooming all one's friends and acquaintances became so time-consuming as to be unaffordable. In response to this problem, Dunbar argues that humans invented 'a cheap and ultra-efficient form of grooming'—''vocal grooming.'' To keep allies happy, one now needs only to 'groom' th ...
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Nomad
A nomad is a member of a community without fixed habitation who regularly moves to and from the same areas. Such groups include hunter-gatherers, pastoral nomads (owning livestock), tinkers and trader nomads. In the twentieth century, the population of nomadic pastoral tribes slowly decreased, reaching an estimated 30–40 million nomads in the world . Nomadic hunting and gathering—following seasonally available wild plants and game—is by far the oldest human subsistence method. Pastoralists raise herds of domesticated livestock, driving or accompanying them in patterns that normally avoid depleting pastures beyond their ability to recover. Nomadism is also a lifestyle adapted to infertile regions such as steppe, tundra, or desert, ice and sand, where mobility is the most efficient strategy for exploiting scarce resources. For example, many groups living in the tundra are reindeer herders and are semi-nomadic, following forage for their animals. Sometimes also described as ...
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Subsistence Farming
Subsistence agriculture occurs when farmers grow food crops to meet the needs of themselves and their families on smallholdings. Subsistence agriculturalists target farm output for survival and for mostly local requirements, with little or no surplus. Planting decisions occur principally with an eye toward what the family will need during the coming year, and only secondarily toward market prices. Tony Waters, a professor of sociology, defines "subsistence peasants" as "people who grow what they eat, build their own houses, and live without regularly making purchases in the marketplace." Despite the self-sufficiency in subsistence farming, most subsistence farmers also participate in trade to some degree. Although their amount of trade as measured in cash is less than that of consumers in countries with modern complex markets, they use these markets mainly to obtain goods, not to generate income for food; these goods are typically not necessary for survival and may include sugar ...
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Company (military Unit)
A company is a military unit, typically consisting of 80–250 soldiers and usually commanded by a major or a captain. Most companies are formed of three to seven platoons, although the exact number may vary by country, unit type, and structure. Usually several companies are grouped as a battalion or regiment, the latter of which is sometimes formed by several battalions. Occasionally, ''independent'' or ''separate'' companies are organized for special purposes, such as the 1st Air Naval Gunfire Liaison Company or the 3rd Force Reconnaissance Company. These companies are not organic to a battalion or regiment, but rather report directly to a higher level organization such as a Marine Expeditionary Force headquarters (i.e., a corps-level command). Historical background The modern military company became popularized during the reorganization of the Swedish Army in 1631 under King Gustav II Adolph. For administrative purposes, the infantry was divided into companies consist ...
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Modern World
The term modern period or modern era (sometimes also called modern history or modern times) is the period of history that succeeds the Middle Ages (which ended approximately 1500 AD). This terminology is a historical periodization that is applied primarily to European and Western history. The modern era can be further divided as follows: * The early modern period lasted from c. AD 1500 to 1800 and resulted in wide-ranging intellectual, political and economic change. It brought with it the Age of Enlightenment, the Industrial Revolution and an Age of Revolutions, beginning with those in America and France and later spreading in other countries, partly as a result of upheavals of the Napoleonic Wars. * The late modern period began around 1800 with the end of the political revolutions in the late 18th century and involved the transition from a world dominated by imperial and colonial powers into one of nations and nationhood following the two great world wars, World War I and W ...
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Ancient Rome
In modern historiography, ancient Rome refers to Roman civilisation from the founding of the city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD. It encompasses the Roman Kingdom (753–509 BC), Roman Republic (509–27 BC) and Roman Empire (27 BC–476 AD) until the fall of the western empire. Ancient Rome began as an Italic settlement, traditionally dated to 753 BC, beside the River Tiber in the Italian Peninsula. The settlement grew into the city and polity of Rome, and came to control its neighbours through a combination of treaties and military strength. It eventually dominated the Italian Peninsula, assimilated the Greek culture of southern Italy ( Magna Grecia) and the Etruscan culture and acquired an Empire that took in much of Europe and the lands and peoples surrounding the Mediterranean Sea. It was among the largest empires in the ancient world, with an estimated 50 to 90 million inhabitants, roughly 20% of t ...
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Army
An army (from Old French ''armee'', itself derived from the Latin verb ''armāre'', meaning "to arm", and related to the Latin noun ''arma'', meaning "arms" or "weapons"), ground force or land force is a fighting force that fights primarily on land. In the broadest sense, it is the land-based military branch, service branch or armed service of a nation or country. It may also include aviation assets by possessing an army aviation component. Within a national military force, the word army may also mean a field army. In some countries, such as France and China, the term "army", especially in its plural form "armies", has the broader meaning of armed forces as a whole, while retaining the colloquial sense of land forces. To differentiate the colloquial army from the formal concept of military force, the term is qualified, for example in France the land force is called ''Armée de terre'', meaning Land Army, and the air and space force is called ''Armée de l'Air et de l’Esp ...
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Hutterite
Hutterites (german: link=no, Hutterer), also called Hutterian Brethren (German: ), are a communal ethnoreligious group, ethnoreligious branch of Anabaptism, Anabaptists, who, like the Amish and Mennonites, trace their roots to the Radical Reformation of the early 16th century and have formed intentional communities. The founder of the Hutterites, Jacob Hutter, "established the Hutterite colonies on the basis of the Schleitheim Confession, a classic Anabaptist statement of faith" of 1527, and the first communes were formed in 1528. Since the death of Hutter in 1536, the beliefs of the Hutterites, especially those espousing a community of goods and nonresistance, have resulted in hundreds of years of diaspora in many countries. The Hutterites embarked on a series of migrations through central and eastern Europe. Nearly extinct by the 18th century, they migrated to Russian Empire, Russia in 1770 and about a hundred years later to North America. Over the course of 140 years, their p ...
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