POPULATION
POPULATION AND HEALTH
“You are one in a million, there are 1700 people in China exactly like you.”
In this chapter we will look at the human
population. We’ll look at the size of it, and
whether it may be growing or shrinking.
We’ll explore the role of scale. We’ll look at
differences between countries. And we’ll do
all of this through the lens of spatiality.
The human population is at 7.5 billion, an
all-time high. In the space of a few centuries it
has gone from less than one billion to more than
seven, with projections of several billions more
in the relatively near future (Figure 2.2).
At the global level we can talk about population
without consideration of migration,
since the earth is a closed system in this
regard, but when we discuss countries, it is
useful to separate the natural increase
rate—the rate of population change only
accounting for births and deaths—from the
effect of migration. A full discussion of migration
occurs in Chapter Three. The following map shows a choropleth map of countries
of the world categorized by population (Figure 2.3). Notice Bangladesh, the
small country nearly surrounded by India.
Hold that in your mind while you look at Figure 2.4. Although they are vastly
different in size, the population of Bangladesh is almost 20 million larger than
Russia. Not only that, but the population of Russia is shrinking and the population
of Bangladesh is growing!
As Figure 2.3 showed there are
some spatial patterns that present themselves,
but there is a great deal of noise
in the signal. Many of the countries with
large populations are physically large
themselves. Places like China and India
have had comparably large populations
for a long time. Very often, explorations
of population growth are short circuited
by discussions of religion or levels of
development. Although religion and development
are not irrelevant, they are
not as important as is often assumed.
Individual characteristics have come to
mean less than they have in the past.
The most obvious characteristic that often leads to higher population growth is
poverty. There are many reasons for this, two of which were mentioned previously,
but there are others. The effect of infant mortality drives some people to have
a large number of children in the forlorn hope that some of them survive to
adulthood. Another is the effect of migration, which can boost incomes by sending
some population to other countries to work, but depopulate the places that are
sending migrants.
In almost all countries, the rate of population growth has slowed. Two countries,
China and India, account for 36 percent of the world’s population. Any change
in these two places will have a large impact on the values for the entire planet.
According to the World Bank for 2013, the population of China is growing .5
percent per year, India is growing 1.2 percent per year, the United States is growing
by .7 percent per year, and Indonesia is growing by 1.2 percent per year. The rates
for all these countries have been falling for decades, even Indonesia and India.
The populations of the countries of Japan, Russia, Germany, Spain, and Ukraine
are all shrinking whereas the populations of Nigeria, the Democratic Republic of
Congo, Iraq, and Kenya are expanding rapidly (Figure 2.5). In developed countries,
population decline has implications for social programs such as retirement, which is
funded by a shrinking pool of workers. In very advanced societies, a worker shortage
is driving rapid development of robotics. In poorer places rapid population growth
can trigger large-scale migration and social disruption.
Why is it so difficult to find one characteristic that explains the population
dynamics of a particular country? Because places matter. Each place is a unique
combination of factors, and their interactions.
THINKING ABOUT POPULATION
No discussion of population is complete without a brief history of the
philosophical understanding of population. This discussion starts as it often does,
with the ancient Greeks. The Greeks considered that they lived in the best place on
Earth. In fact, they believed in the exact center of the habitable part of the Earth.
They called the habitable part of the Earth ecumene. To the Greeks, places north
of them were too cold, and places to the south were too hot. Placing your own
homeland in the center of goodness is common; many groups have done this. The
Greeks decided that the environment explained the distribution of people. To an
extent, their thinking persists, but only at the most extreme definitions. Many
places that the Greeks would have found too cold (Moscow, Stockholm) too hot
(Kuwait City, Las Vegas) too wet (Manaus, Singapore) or too dry (Timbuktu, Lima)
have very large populations.
2.2.2 Modern Ideas About Population
Thomas Malthus (1766-1834) “Population, when unchecked, increases in a
geometrical ratio.” 4
Ester Boserup (1910-1999) “The power of ingenuity would always outmatch
that of demand.”
FOOD WITH POPULATION
Modern discussions of population begin with food. From the time of Thomas
Malthus (quoted above), modern humans have acknowledged the rapidly expanding
human population and its relationship with the food supply. Malthus himself was
a cleric in England who spent much of his time studying political economy. His
views were a product not only of his time, but also of his place. In Malthus’ case his
time and place were a time of social, political, and economic change.
Karl Marx (1818–1883) took issue with Malthus’ ideas. Marx wrote that
population growth alone was not responsible for a population’s inability to feed
itself, but that imbalanced social, political, and economic structures created
artificial shortages. He also believed that growing populations reinforced the
power of capitalists, since large pools of underemployed laborers could more easily
be exploited.
The post-World War II period saw a flurry of books warning of the dangers
of population growth with books like Fairfield Osborn’s Our Plundered Planet
and William Vogt’s Road to Survival. Perhaps most explicit was Paul and Anne
Ehrlich’s The Population Bomb.
These books are warnings of the dangers of unchecked population growth.
Malthus wrote that populations tend to grow faster than the expansion of food
production and that populations will grow until they outstrip their food supplies.
This is to say that starvation, war, and disease were all predictions of Malthus
and were revived in these Neo-Malthusian publications. Some part of the current
conversation of environmentalism regards limiting the growth of the human
population, echoing Malthus.
A common theme of these books is that they all attempt to predict the future.
One of the advantages we have living centuries or decades after these books is the
opportunity to see if these predictions were accurate or not. Ehrlich’s book predicted
that by the 1970s, starvation would be widespread because of food shortages and
a collapse in food production. That did not happen. In fact, the global disasters
predicted in all these books have yet to arrive decades later. What saved us?
Perhaps nothing has saved us. We have just managed to push the reckoning a
bit further down the road.
If we have been saved, then the assumptions inherent in the predictions were
wrong. What were they?
- Humans would not voluntarily limit their reproduction.
- Farming technology would suddenly stop advancing.
- Food distribution systems would not improve.
- Land would become unusable from overuse.
All of these assumptions have proven to be wrong, at least so far. Only the most
negative interpretation of any particular factor in this equation could be accepted.
One the other hand, Ester Boserup, an agricultural economist in the twentieth
century, drew nearly the opposite conclusion from her study of human population.
Her reason for doing so were manifold. First, she was born one and one -half
centuries later, which gave her considerably more data to interpret. Second,
she didn’t grow to adulthood in the center of a burgeoning empire. She was a
functionary in the early days of the United Nations. Third, she was a trained as an
economist, and finally, she was a woman. Each one of these factors was important.
2.2.3 Let’s Investigate Each One of These Assumptions
In preindustrial societies, children are a workforce and a retirement plan.
Families can try to use large numbers of children to improve their economic
prospects. Children are literally an economic asset. Birth rates fall when societies
industrialize. They fall dramatically when women enter the paid workforce. Children
in industrialized societies are generally not working and are not economic assets.
The focus in such societies tends to be preparing children through education for a
technologically-skilled livelihood. Developed societies tend to care for their elderly
population, decreasing the need for a large family. Developed societies also have
lower rates of infant mortality, meaning that more children survive to adulthood.
The increasing social power of women factors into this. Women who control
their own lives rarely choose to have large numbers of children. Related to this,
the invention and distribution of birth control technologies has reduced human
numbers in places where it is available.
Farming technology has increased tremendously. More food is now produced
on less land than was farmed a century ago. Some of these increases are due to
manipulations of the food itself—more productive seeds and pesticides, but some
part of this is due to improvements in food processing and distribution. Just think
of the advantages that refrigeration, freezing, canning and dehydrating have given
us. Add to that the ability to move food tremendous distances at relatively low cost.
Somehow, during the time that all these technologies were becoming available,
Neo-Malthusians were discounting them.
Some marginal land has become unusable, either through desertification or
erosion, but this land was not particularly productive anyway, hence the term marginal.
The loss of this land has been more than compensated by improved production.
At this point, it looks like a win for Boserup, but maybe it isn’t. Up to this point
we have been mixing our discussions of scale. Malthus was largely writing about
the British Isles, and Boserup was really writing about the developed countries of
the world. The local realities can be much more complex.
At the global scale there is enough food, and that has been true for decades. In
fact, many developed societies produce more food than they can either consume
or sell. The local situation is completely different. There are developed countries
that have been unable to grow food to feed themselves for over a century. The
United Kingdom, Malthus’ home, is one of them. However, no one ever calls the
U.K. overpopulated. Why not? Because they can buy food on the world market.