Editing Human migration (section)

== Historical theories ==

=== Ravenstein ===
{{unreferenced section|date=May 2020}}
Certain laws of [[social sciences|social science]] have been proposed to describe human migration. The following was a standard list after [[Ernst Georg Ravenstein]]'s proposal in the 1880s:

# every migration flow generates a return or counter migration.
# the majority of migrants move a short distance.
# migrants who move longer distances tend to choose big-city destinations.
# urban residents are often less migratory than inhabitants of rural areas.
# families are less likely to make international moves than young adults.
# most migrants are adults.
# large towns grow by migration rather than natural increase.
# migration stage by stage ([[step migration]]).
# urban, rural difference.
# migration and technology.
# economic condition.

=== Push and pull ===
Demographer Everett S. Lee's model divides factors causing migrations into two groups of factors: push and pull. Push factors are things that are unfavourable about the home area that one lives in, and pull factors are things that attract one to another host area.<ref>{{cite journal |jstor=2060063 |title=A Theory of Migration |journal=Demography |first=Everett S. |last=Lee |year=1966 |volume=3 |issue=1 |pages=47–57 |doi=10.2307/2060063 |s2cid=46976641 |doi-access=free}}</ref><ref>Guido Dorigo, and Waldo Tobler, "Push-pull migration laws." ''Annals of the Association of American Geographers'' 73.1 (1983): 1-17 [https://citeseerx.ist.psu.edu/document?repid=rep1&type=pdf&doi=9fc54ac2a2b06286b10ebf873e6a227b4bf43953 online]</ref>

'''Push factors''':
{{div col|colwidth=20em}}
* Not enough jobs
* Few opportunities
* Conscription (draft young men into army)
* Famine or drought
* Political fear of persecution
* Poor medical care
* Loss of wealth
* Natural disasters
* Death threats
* Desire for more political or religious freedom
* Pollution
* Poor housing
* Discrimination
* Poor chances of marrying
* War or threat of invasion
* Disease
{{Div col end}}
'''Pull factors''':
{{div col|colwidth=20em}}
* Job opportunities
* Better living conditions
* The feeling of having more political or religious freedom
* Enjoyment
* Education
* Better medical care
* Attractive climates
* Security
* Family links
* Industry
* Better chances of marrying
{{Div col end}}

=== Climate cycles ===
The modern field of climate history suggests that the successive waves of Eurasian nomadic movement throughout history have had their origins in [[Climate change (general concept)|climatic cycles]], which have expanded or contracted pastureland in Central Asia, especially [[Mongolia]] and to its west the [[Altai Mountains]]. People were displaced from their home ground by other tribes trying to find land that essential flocks could graze, each group pushing the next further to the south and west, into the highlands of [[Anatolia]], the [[Pannonian Plain]], into [[Mesopotamia]], or southwards, into the rich pastures of China. Bogumil Terminski uses the term "migratory domino effect" to describe this process in the context of [[Sea People]] invasion.<ref>{{cite book |last=Terminski |first=Bogumil |title=Environmentally-Induced Displacement. Theoretical Frameworks and Current Challenges |publisher=CEDEM, Université de Liège |date=2012}}</ref>

=== Food, sex, and security ===
The theory is that migration occurs because individuals search for food, sex and security outside their usual habitation; Idyorough (2008) believes that towns and cities are a creation of the human struggle to obtain food, sex and security. To produce food, security and reproduction, human beings must, out of necessity, move out of their usual habitation and enter into indispensable social relationships that are cooperative or antagonistic. Human beings also develop the tools and equipment to interact with nature to produce the desired food and security. The improved relationship (cooperative relationships) among human beings and improved technology further conditioned by the push and pull factors all interact together to cause or bring about migration and higher concentration of individuals into towns and cities. The higher the technology of production of food and security and the higher the cooperative relationship among human beings in the production of food and security and the reproduction of the human species, the higher would be the push and pull factors in the migration and concentration of human beings in towns and cities. Countryside, towns and cities do not just exist, but they do so to meet the basic human needs of food, security and the reproduction of the human species. Therefore, migration occurs because individuals search for food, sex and security outside their usual habitation. Social services in the towns and cities are provided to meet these basic needs for human survival and pleasure.<ref>Idyorough, 2008</ref>

=== Other models ===
* [[Zipf's law|Zipf's inverse distance law]] (1956)
* [[Gravity model of migration]] and the [[friction of distance]]
* [[Radiation law for human mobility]]
* [[Buffer theory]]
* Stouffer's [[theory of intervening opportunities]] (1940)
* [[Zelinsky Model|Zelinsky's Mobility Transition Model]] (1971)
* Bauder's regulation of [[labour economics|labour markets]] (2006): "suggests that the international migration of workers is necessary for the survival of industrialised economies...[It] turns the conventional view of international migration on its head: it investigates how migration regulates labour markets, rather than labour markets shaping migration flows."<ref>{{cite book |last=Bauder |first=Harald |title=Labour Movement: How Migration Regulates Labour Markets |publisher=[[Oxford University Press]] |edition= |date=2006 |isbn=978-0195180886}}</ref>