A city's population may be the Rosetta Stone for studies in everything from public policy to global economic predictions. Professors Geoffrey West and Luis Bettencourt at the Santa Fe Institute in New Mexico argue in their paper, "A Unified Theory Of Urban Living," that regardless of "history, geography, or design," they can predict facts about a city -- from GDP, to the rate of AIDS infection, to the speed people walk -- simply by knowing the population of the city.
Bettencourt and West spoke with RFE/RL about how their study can be grafted onto all cities -- developed and developing.
Bettencourt explains that "regardless of how the city looks in space -- like LA or New York -- it doesn't really matter for its economic performance. Over 90 percent [of its economic performance] is determined by population size, whether people live in suburbs or live densely, it doesn't really matter."
In their paper, Bettencourt and West stress that urban growth has been the steam that has propelled both humanity's "creativity," as well as the enzyme that has catalyzed or exponentially aggravated "global problems from climate change and its environmental impacts to incipient crisis in food, energy, and water availability, public health, and financial markets, and the global economy."
As far as positives go, as the population of an area grows, Bettencourt and West say there are three main changes:
First, space required per person shrinks, due to better use of infrastructure. In fact, they argue that when the population of a city doubles, the city only requires an 85 percent increase in infrastructure -- meaning water pipes, gas stations, telephone cables.
Second, "the pace of all socioeconomic activity accelerates," which leads to the creation of more products in a shorter amount of time.
And third, "economic and social activities diversify and become more interdependent," which they argue leads to specialization, and conversely, wide-ranging cultural expression.
"As city size increases, per capita socioeconomic quantities such as wages, GDP, number of patents produced, and number of educational and research institutions all increase by about 15 percent more than the expected linear growth," they write. Good And Bad
Take, for example, Pakistan's largest city, Karachi. In 1950, the official population was around 1.1 million. Currently the administration predicts
that the population is growing at a rate of 5 percent a year, to the hard-to-imagine number of 20 million people, or, as the newspaper "Dawn
" puts it, "45,000 people coming into the city every month from various parts of the country." And this is merely the official estimate, which probably does not account for migrant labor, illegal immigration, or sprawls of urbanizing areas outside Karachi.
In a survey of the projection of the city's GDP rankings in 2050, the British consulting company PricewaterhouseCoopers projects that Karachi, which ranked 78th out of 151 in 2008, will climb to 57th, with a GDP in 2025 of $193 billion.
However, what must not be forgotten is that, as a city grows, that same 15 percent increase is similarly true for negatives -- disease, crime, pollution -- Bettencourt and West say.
As PricewaterhouseCoopers' survey remarks, "Some preliminary analysis we have carried out suggests that emerging-market coastal cities like [...] Karachi could be particularly exposed to any early adverse effects from climate change."
According to government reports
, in 2009-10, Pakistan's GDP increased by 4.1 percent. However, in the same span of time, there were 1,906 recorded terrorist attacks, which killed 1,835 people.
Karachi, as Pakistan's largest city and economic center, reflects both of these statistics. In October, postelection attacks killed around 80 people
, while at the same time a PricewaterhouseCoopers' study done in 2009 projected Karachi's GDP to grow to $193 billion by 2025 -- a growth rate of 5.5 percent, only slightly higher than the population increase of 5 percent -- in agreement with West and Bettencourt's research.
According to West and Bettencourt, cities, not countries, are the "natural socioeconomic units," meaning that cities reflect all of a country's conflicts and cancerous problems, as well as the ways societies work together.
Rapid urbanization, they claim, "brings all these problems [that were there] to the foreground, and if they're not solved, the nation, the city will not grow and [will] struggle."
The crux of the problem, West and Bettencourt say, is how these regions deal with issues, like security and environmental sustainability, as the population grows -- exponentially -- and governments must deal with the problem of how "people can be more productive and not lead to greater social problems."
-- Ashley Cleek