There is a tendency in the migration literature to see rural communities that send many migrants to the United States as closed communities. The theory of cumulative causation rests on the assumption of bounded communities and posits a saturation point at which no more migration from the community occurs. The implication that eventually there will be no further migration from a given community ignores the existence of networks that bind people from nearby or even distant communities which can be tapped by a potential migrant and the phenomenon of internal migration to dynamic rural centers. Migration networks also expand in urban centers through marriages of a family's offspring that bring people without established ties in the US into intimate contact with people who do have these ties. [Keywords: Transnational migration, cumulative causation, network expansion, non-bounded communities, family based social capital]
Foreign language translations:
Cumulative Causation Unbounded: Network Expansion in Rural and Urban Migration Centers
[Keywords: Transnational migration, cumulative causation, network expansion, non-bounded communities, family based social capital]
Causación cumulativa sin fronteras: La expansion de redes en centros de migración rurales y urbanas
[Palabras clave: migración internacional, causación cumulativa, redes migratorias, redes de asociación, expansión de redes]
Casualidade Cumulativa Sem Limites: A Expanção de Redes Socias nos Centros Rurais e Urbanos
[Palavras chaves: Migração transnacional, casualidade cumulativa, expansão de redes sociais, communidades abertas, capital social familiar
(ProQuest: ... denotes non-US-ASCII text omitted.)
The dynamics of family, social, and community networks in transnational migration between Mexican rural communities and the US has been explored in great depth in the migration literature for a little more than two decades (e.g., Cornelius 1991; Durand and Massey 1992; Kearney 1986, 1991; Massey 1987; Massey and Espinosa 1997; Massey and García España 1987; Massey et al. 1987; Massey, Goldring, and Durand 1994; Mines and Massey 1985; Nuñez and Heyman 2007; Portes and Bach 1985; Wilson, 1992, 1993, 1994, 1998, 2006; and others). It has been widely argued that transnational migration begins among pioneering immigrants economically capable of affording the costs of the trip north and the risks of failure. The pioneering migrants are usually young men, but as networks linking origin and destination communities mature and a settlement process occurs, the landless, less well off, women, and children are also incorporated into the migration stream (e.g., Durand and Massey 1992; Massey and Espinosa 1997; Massey, Goldring, and Durand 1994). Eventually, as Massey and his colleagues show, with the maturation of migration networks, migration becomes a relatively lowcost, low-risk strategy for all members of the community (e.g., Durand and Massey 1992). Thus the migration process is cumulative: as a former migrant aids new migrants, s/he will in turn extend aid in the migration process to other members of her/his network.
The "saturation point thesis," a corollary to this cumulative causation thesis, predicts that once every member of a given community has network ties to the US, when larger and larger numbers of community members reside abroad, and when prevalence rates for migration reach approximately 80 percent among males "networks reach a point of numerical saturation" and "the process of migration loses its dynamic momentum for growth" (Massey, Goldring, and Durand 1994:1502-1503).
In a more recent work Massey et al. (2003:20, emphasis added) reiterate their "saturation" thesis: "In any bounded population...processes of cumulative causation cannot continue ad infinitum. If migration continues long enough, networks eventually reach a point of saturation within any particular community. …