The Global Urbanist

News and analysis of cities around the world

Africa's Urban Revolution, part 2: de-urbanisation is futile

In this second instalment of a two-part review of Africa’s Urban Revolution, Kerwin Datu considers Sean Fox’s provocative new theory that urbanisation is driven by demographic transition, not by economic growth, and that even rural development initiatives will directly cause increased urban populations regardless of where and whether economic opportunities even exist.

Kerwin Datu

Kerwin Datu

Cities: Cape Town

Topics: Integrated planning, Regional governance, Urban economics, Development

The African Centre for Cities’ (ACC) new collection of essays Africa’s Urban Revolution (Zed Books) proposes a number of advances to both the policy and theory of Africa’s urbanisation experience in issues such as decentralisation, food security and armed conflict as the first part of this review learnt.

Two further chapters address an empirical problem that has always grated with economic geographers and which has very deep implications for all of the regulatory issues raised in the previous instalment. The massive urbanisation experienced in Western Europe, North America and East Asia as each of these regions underwent industrialisation in past centuries has cemented in place the theory that urbanisation is caused essentially by economic growth, that “growth begets urbanisation”. A major exception has been Sub-Saharan Africa, especially during the 1980s and 1990s, during which World Bank economists Marianne Fay and Charlotte Opal observed that “urbanisation continues even during periods of negative (economic growth)”, somehow continuing simply under its own momentum. In a sense, they argued at the time that: “urbanisation begets urbanisation”.

Despite this inexplicable exception, the theory that “growth begets urbanisation” has persisted, and in recent years been turned on its head to become the “urbanisation begets growth” mantra of the “urban prosperity” cheer squad. This notion, cherished by rather a lot of urban development agencies as well as pro-city neoliberals such as Ed Glaeser, is that if urbanisation is allowed to proceed in a sustainable fashion, economic growth will follow.

Indeed, since urbanisation has proven almost completely inevitable, shaping it into sustainable patterns of development is the least we must do to prevent the tragedy Edgar Pieterse, director of the ACC, warns of in this book, but this does not mean that economic growth follows just as inevitably. In Africa’s Urban Revolution, Ivan Turok’s chapter re-examines this mantra in light of the most recent data, finding that evidence points in both directions at once. It is not urbanisation per se that encourages growth but rather active policy measures that improve the diversity and productivity of urban areas and their residents, the benefits of which are most evident precisely when they are implemented in the context of growing cities.

Demography, not growth, begets urbanisation

But the most provocative and important chapter in Africa’s Urban Revolution is that by Sean Fox, which shakes to the core the much more robust “growth begets urbanisation” theory itself. The measure of an excellent scientific theory is that it explains all that previous theories explain as well as explaining all major exceptions that challenged those previous theories, all the while doing so in terms as simple as previous theories. Fox’s brilliant theory which does all this is as follows: demography begets urbanisation. Or, in a slightly expanded formulation, the onset of the demographic transition may trigger both increased urban populations as well as increased opportunities for economic growth. But while demographic transition is a sufficient condition for urbanisation, it is not a sufficient condition for economic growth, meaning that urbanisation can arise even when economic growth does not.

Unpacking what the field of demography has to say about historical levels of urbanisation in various regions of the world, he identifies that major episodes of urbanisation, whether accompanied by episodes of economic growth or not, have been preceded by a major demographic transition. For most of human history, cities have been “demographic sinks”, places where only a few hardy souls convened for what opportunities for prosperity existed despite urban areas being “deadly places in which to live”. “Before the nineteenth century, urban settlements with rudimentary water and sanitation infrastructures were especially conducive to the spread of infectious and parasitic diseases. As a consequence, death rates tended to exceed birth rates”. Megacities, especially those with sophisticated infrastructure such as ancient Rome, were the exception rather than the rule they have become today.

Interestingly, and importantly for Africa’s urban denialists, this meant that “cities depended on a constant inflow of rural migrants to sustain their populations. This suggests that the propensity to migrate from rural to urban settlements has been a consistent feature of human behaviour for as long as cities have existed – even when migrants stood to suffer from higher rates of morbidity and mortality than they would have done in the countryside.” And remember that cities have existed in Africa for up to 2,000 years, especially in the Niger River’s “inland delta” in today’s Mali.

A series of changes in technology and social structure began to set demographic transitions in motion around the world, first in Western Europe, then across other continents. “Innovations such as nitrogen fertiliser, crop rotation and mechanisation drove a surge of agricultural productivity … the harnessing of inanimate sources of energy … led to a dramatic reduction in transportation costs … improvements in hygiene, medical knowledge, maternal education and urban planning practices and the expanded availability of healthcare led to a gradual decline in mortality rates … political-institutional changes such as the consolidation of private property rights, improved third party contract enforcement, and an expansion of the role of governments in the provision of public goods (notably healthcare, education and infrastructure) reinforced and sustained these trends.”

The improvement of health conditions caused mortality to drop, producing population booms in both rural and urban areas, while at the same time making urban areas more habitable, and thus relatively more attractive. Improvements in agricultural technology made rural areas more productive, meaning that they required fewer rural workers to achieve the same output, again causing more of them to seek opportunity in urban areas, regardless of whether those opportunities exist. But where they did, improvements in legal institutions allowed the majority of these new urban communities to develop and exploit new opportunities in the security of relatively low-risk conditions. As falling death rates proved to sustain themselves, families became content with fewer children, lowering birth rates as well. But not before urban populations had boomed, regardless of the economic opportunities that existed for them.

As Fox continues, in colonial-era Africa many of these technological and sanitary improvements were introduced by colonial powers, providing the initial spark for demographic transitions across the continent, yet the legal institutions required for growing indigenous urban populations to capitalise economically on the demographic boom were often withheld from them by the same powers. In the post-colonial era this pattern was often sustained where unequal access to formal opportunities persisted while agricultural and sanitary improvements continued to be introduced (including by foreign donors) that allowed the demographic transition to continue.

Even rural development causes urbanisation

There are several lessons that African authorities and the international agencies who support them must desperately learn if Fox’s theory proves robust. First, his theory states precisely that improvements to rural areas directly contribute to increased urban populations. Therefore the attempts made by African governments to minimise urbanisation by improving rural areas is counterproductive to their aims. As Fox was quick to clarify at the Africa Research Institute launch, this does not mean that African governments should not bother with improvements to rural areas, especially as they desperately need them. Rather, they should do so only out of desire to improve conditions for rural constituencies, not in futile attempts to trigger de-urbanisation.

In fact, Fox’s theory implies that the only way to trigger de-urbanisation is to seriously trash one’s own agricultural surpluses and hygiene conditions, which even the most ardently anti-urban leaders would be unlikely to consider.  An example that he provides where this happened by accident is Zambia in the 1980s and 1990s. While economic woes plagued several African countries during this time, only Zambia experienced significant de-urbanisation as predicted by the inverse of the “growth begets urbanisation” theory that has prevailed until now (that is, that “a reversal of growth begets a reversal of urbanisation”). Fox shows that even this is better understood as a demographic phenomenon. While many countries’ economies declined, only Zambia also suffered “a sharp decline in food supplies and a reversal in the trend of declining mortality … as a result of a crisis in the public health sector, deteriorating nutrition and increases in mortality related to malaria and HIV/Aids in particular”. Fox continues: “In other words, Zambia experienced a unique combination of misfortunes that led to the resurgence of the surplus and disease constraints that inhibit urbanisation—and in this case resulted in a rare episode of de-urbanisation.”

The final lesson is, as Pieterse and the other authors of Africa’s Urban Revolution have argued by other means, that Africa’s cities need to give up obsessing with trying to prevent urban growth, and direct policies towards ensuring that urbanisation occurs in sustainable ways. As Turok argues, policies need to focus on improving the economic productivity of urban areas, strengthening the legal institutions that protect urban residents and entrepreneurs whatever their background, thus finally transforming Africa’s urban demographic boom into the urban economic boom it deserves.


is editor-in-chief of The Global Urbanist.

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