"Those that do will unlock the full potential of the urban revolution," he wrote recently. "Those that do not will fall behind."
Muggah said officials who can get their hands on data about urbanization and fragility have a responsibility to implement creative solutions.
His research has found that improving social cohesion through consistent increases in public transit and affordable housing builds trust among residents in cities like Bogota, Juarez, and São Paulo, Brazil. In addition, regulating drugs through pharmacies and decriminalization help reduce drug trafficking.
Source: Igarapé Institute
Muggah views the gains made in Latin America — another fragile region, where 47 of the 50-most murderous cities on Earth are located — as a sign that fragile cities elsewhere could slow their urban expansion and safeguard their future.
Source: World Economic Forum
Muggah doesn't see an end in sight just yet. Roughly 25% of all low-income cities became more fragile over the last 15 years, his analysis shows, as fragility increases in cities that are growing the fastest.
These fragile cities also have high unemployment and crime rates. In Mogadishu, Somalia, for instance, the unemployment rate is 66%. It is the most fragile city in the world.
Source: Business Insider
Ultimately, the result is the proliferation of crowded cities that can't handle millions of new residents, both native-born and those moving in from surrounding rural areas.
The story has been the same since 1960. Most of the 10 nations with the highest fertility rates have been in Africa. Public health experts have tried to make inroads with contraception strategies and education, but many parents still have numerous kids.
Source: World Bank, Johns Hopkins University
High fertility rates are a major factor. Nigeria's fertility rate has fallen over the past 60 years, but still sits at 5.4 children per woman. Demographers say the ideal number for keeping populations steady is 2.2 children per woman.
Source: World Bank
"Urbanization without industrialization," or the growth of cities without infrastructure to support new populations, may be to blame, Muggah said at a recent TED Global event.
By 2015, Lagos's population had ballooned to 17.9 million. By 2050, it could be double that. According to Muggah's analysis, the past 15 years have seen the city grow far more fragile.
Source: World Population Review
Lagos, Nigeria is perhaps Africa's best case study for the continent's ongoing urbanization challenges. In 2000 (depicted below) the population was 7.2 million. It was moderately fragile.
One of the best ways to view the impact of urban expansion is with Earth Timelapse, a tool Muggah helped create. The below image shows a 2015 map of urbanizing areas, which are lit up, and fragile cities with colored dots. The darker the dot, the more fragile the city.
Source: Business Insider India