Population, territory and sustainable development

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As table X.4 shows, during the period of study, a large number of urban areas joined the ranks of
cities with between 1 and 4 million inhabitants, compared with just one in 1950. In addition, these cities’
populations have generally grown faster than those of in the metropolises, a phenomenon that Rodríguez
and Villa had already attributed back in 1998 to heavy migration to these cities from the 1950s to the
1970s. Despite this phenomenon and as with the metropolises, natural population growth has been a
progressively less important factor in the demographic growth of most large cities.
Population growth in most national capitals topped 2.5% during the last intercensal period, proof
that these cities are still a migration magnet. Moreover, a recent study by Rodríguez (2009) states that
“most of these cities continue to have net positive migration, which points to the continued preeminence
and attractiveness of this superior segment of the region’s urban systems.” This phenomenon is plain to
see in Guatemala City, Santo Domingo, Port-au-Prince, Asunción, La Paz, Panama City and San José.
Large cities in border areas or regions with historically low population presented high growth
rates (over 3.8%) during virtually the entire period of study, and net positive migration is observed in all
of them. In Mexico, Ciudad Juaréz and Tijuana receive immigrants from every corner of the country and
even from other countries in Central America, due to their location on the border with the United States.
Brazil’s large cities offer another example of net positive migration. Brasilia is a clear example of a large
city experiencing population growth and inflows of migrants, while Belém and Manaos offer an alternate
destination for the migratory flows to the country’s large metropolises.
There are cities that have grown quickly during the period under consideration based on their
power to attract migrants, which can be attributed to a number of factors, including a local economy
driven by trade (Guayaquil and Maracaibo) or the presence of industrial conglomerates (Vitoria, Curitiba,
Guadalajara and Monterrey). Growth in other cities has been driven by their proximity to a capital city
(Campinas and Santos in Brazil, Puebla in Mexico).
In short, although large cities are undeniably diverse in terms of demographic growth, generally
speaking they all have above-average demographic growth rates. The fact that growth is much slower now
than two or three decades ago reflects not a loss of attractiveness to migrants, but rather the progression of
a demographic transition and a reduction in migratory flows. Metropolises and megalopolises are the
exception. Aside from Lima, Bogota and perhaps Buenos Aires, population growth in these cities is not
keeping pace with national averages, and in fact they are experiencing net out-migration.
2. Figures and debate on the primacy and development of large cities
The hegemony of large cities has another manifestation: the existence in most of the region’s countries of
highly polarized (“high primacy”) urban systems in which one or two cities far surpass the rest in terms of
number of inhabitants and factors such as productive capacity, political power, key institutions and
infrastructures.
Not all countries are in this situation, whether due to the prevalence of another territorial
distribution model (simultaneous dominance of two cities in Ecuador, Brazil and the Plurinational State of
Bolivia, and of four cities in Colombia) or the existence of an urban system with numerous interlinking
nodes that counterbalance the importance of the capital city, such as in Mexico (CONAPO, 2001 and
Tuirán, 2000). A comparison of primacy ratios illustrates this situation and indicates that the region stands
apart in this regard from the rest of the world (see figure X.1). Indeed, ratios of greater than two are the
exception in the rest of the world but the rule in Latin America and the Caribbean.