Among the many myths perpetuated about migration, one of the most common is that ‘South–North’ migration is essentially driven by poverty and underdevelopment. Consequently, it is often argued that stimulating economic development would reduce migration from developing countries to North America and Europe. However, this ignores evidence that most migration neither occurs from the poorest countries nor from the poorest segments of the population.
In fact, the paradox is that development and modernization initially leads to more migration. Historical experiences show that societies go through migration transitions as part of broader development processes. In his The Hypothesis of the Mobility Transition, a seminal article published in 1971, the geographer Wilbur Zelinsky argued that all forms of internal and international mobility accelerated when countries start to transition from rural-agrarian to urban-industrial societies.
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| The Migration Transition |
This has been confirmed by various historical studies. For instance, tn their classic study of large-scale European migration to North America between 1850 and 1913, The Age of Mass Migration published in 1998, economic historians Timothy Hatton and Jeffrey Williamson showed that trans-Atlantic migration was driven by the mass arrival of cohorts of young workers on the labour market, increasing incomes and a structural shift of labour out of agriculture towards the urban sector. The rapidly industrializing Northwestern European nations therefore initially dominated migration to North America, with lesser developed Eastern and Southern European nations following suit only later.
This pattern also applies to contemporary migration. As societies develop, they go through migration transitions, leading to a accelerating emigration. This is a long-term, structural relation. Unlike temporary 'migration humps' generated by economic or political shocks, development-driven increases in emigration linked to the migration transition tend to last for several generations.
Recent advances in data and analysis have improved insights about the relationship between development and migration. In 2010, newly available global data on migrant populations enabled me to do a first global assessment of the relationship between levels of development and migration. The graph below shows how levels of emigration and immigration are related to development levels, as measured by the Human Development Index (HDI).
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| de Haas, H. (2010) Migration Transitions. University of Oxford, International Migration Institute |
The pattern for immigration is linear and intuitive: more developed countries attract more migrants. The relation between levels of human development and emigration is non-linear and counter-intuitive: middle-income countries tend to have the highest emigration levels. This pattern also held when using per capita income levels as a measures for development levels.
This finding has been confirmed by later studies (for instance, see here and here) which replicated and expanded my original analysis using global migration data covering the 1960–2015 period. These all demonstrate that increases in levels of economic and human development are initially associated with higher levels of emigration. It is therefore no coincidence that important emigration countries, such as Mexico, Morocco, Tunisia, Turkey, the Philippines and Indonesia are typically middle-income countries.
Only when countries achieve upper-middle to higher income status, such as has recently been the case with Mexico and Turkey, does emigration decrease alongside increasing immigration, leading to their transformation from countries of net emigration to countries of net immigration. In a recent study, Michael Clemens estimated that, on average, emigration starts to decrease if countries cross a wealth-threshold of per-capita GDP income levels of $7,000–8,000 (corrected for purchasing power parity), which is roughly the current GDP level of India, the Philippines and Morocco.
Development in low-income countries boosts internal and international migration because improvements in income, infrastructure and education typically increase people’s capabilities and aspirations to migrate. Particularly international migration involves significant costs and risks which the poorest generally cannot afford, while education and access to information tends to increases people’s material aspirations.
Education and media exposure also typically accelerate cultural change which changes people of the ‘good life’ away from rural and agrarian lifestyles towards urban lifestyles and jobs in the industrial and service sectors. The inevitable result is increasing migration to towns, cities and foreign lands.
Middle-income countries therefore tend to be the most migratory and international migrants predominantly come from relatively better-off sections of origin populations. Although these are averages that cannot be blindly applied to individual countries, it seems therefore very likely that any form of development in low-income countries such as in sub-Saharan Africa, South- and South-East Asia and Central America will lead to more emigration in the foreseeable future.
* This text partly draws on the sixth edition of The Age of Migration, a textbook on migration published in 2020, see age-of-migration.com. An earlier version of this blog appeared here.
