Thinking About Population

IREL 204 World Geography

A few statistics• The total population of the world, projected to 10/21/09 is

6,791,823,157 *

• By 2011, the world population is expected to reach 7 billion.

• By 2050, 9.3 billion. • 2008 was the year that half of the world’s population became URBAN –

this means that roughly 3,395,911,578 people live in cities around the world.

• For this portion on Human Populations – which links neatly with our study of human-environment interaction, place and movement – the last three themes of Geography – we will look at WHERE and WHY global populations are where they are, HOW they are distributed, and what processes (like Migration or Human Mobility) drive these types of population trends.

*International Programs Center, U.S. Census Bureau

Human Population• Homo Sapiens – our species – emerged in Africa approximately

200,000 years ago

• From that time onward, human population growth was slow, with human numbers rising and falling due to “traditional” controllers of population growth: – environmental change– disease– and availability of food

• When the Holocene period began (approximately 12,000 - 10,000 years ago) two remarkable things happened:– The last ice age retreated, freeing up greater space that people could

inhabit• So we see here the importance of the physical environment in ‘determining’ – to

a degree – WHERE human settlements can and cannot take root

– Humans began the great experiment known as “Agriculture”.

Early Human Populations

• Initially, humans were hunters and gatherers:– Lived in small groups– Dependent on the physical landscape for shelter• Lived in caves• Used rocks, branches & leaves, animal hides for make-

shift shelters– Nomadic (moving when food supply ran out in a

given location)• Hunted animals, fished• Collected nuts & berries

Agriculture

Source: http://www.museum.agropolis.fr/english/pages/expos/fresque/la_fresque.htm

• At about the year 10,000 the first traces of agriculture were recorded

• Though humans had domesticated certain animals before then, this is the time humans begin herding, nurturing and breeding animals (animal husbandry)

• This period known as the Agricultural Period would last roughly up until the 19th century

Map of early agricultural and animal-domestication centers of the world (Source: Archaeology, 5th Edition: Kelly, R, Thomas, D. (2010). At http://www.dirtbrothers.org/college/introarchaeology002.html)

• Notice that the 7 original cultural hearths (innovative centers of culture) are located in the almost the precise areas of the original “agricultural” hearths (centers of agricultural activity)

•As humans gradually discovered technology and developed tools for securing larger and larger quantities of food – (for the long term, through farming) human societies settled and in so doing, culture as we understand it came into being

AGRICULTURAL CENTERS &

The Industrial Revolution• Agricultural patterns remained roughly stable through

most of human history until the Industrial Revolution in the 19th century

• Human populations began to grow, having overcome, in large part, the problem of “food availability” by creating surpluses– However the traditional controllers of “physical environment”

and “disease” were still keeping populations at a slow growing pace• Plagues, etc

• The Industrial Revolution spawned the beginning of mechanization and mass production, which in turn drove the urbanization process faster than any other time in history

• Advances in technology coincided with the 2nd Agricultural Revolution, more efficient farming practices, introduction of new crops, cross-breeding, better animal husbandry practices

• The process of manufacturing drove, in large part, the change of human settlements from rural to urban (as more people flocked to cities for new labor)

• With fast-paced urbanization, social and cultural changes followed:– Harnessing coal as an energy source

• For factories, etc• Transportation (trains, ships, etc)

– Electricity– Milestones in health

• standardized medical practices • vaccinations • Sanitation

– The Emergence of a “Mass Society”• Urban societies, of the ‘masses’ with socio-political and economic changes reflecting the

impact of technological advance - More inclusive societies - Formation of worker unions,

• Mechanical means substituted human skill• Inanimate power substituted human and animal power• New machines led to improvements in all aspects of life

– Coal mining• Steam

– Railroads (transportation) linking greater and greater distances – Unifying an area– One market– Bridge Building

• All these contributed to less human labor, greater speed and efficiency in production, greater number of goods produced, and speed in transporting goods from point of production to point of consumption – the new, vibrant urban centers

• With transportation, communication technologies soon proliferated– The telegraph and telephone were already becoming part of human

life by the mid to late 19th century

The effect of technology on human populations• Thus the Industrial Revolution challenged the traditional

controllers of population growth:– Humans were now driving the changes in environment, as

the physical landscape was being modified, re-shaped, as bridges were built, canals were dug, mountains were drilled• The physical environment was no longer that important in

determining where people can or cannot settle– More land was available, and the means to get from place to place became

more and more accessible with trains and ships

– Disease was being prevented and systematically studied more than ever before that point in history• Immunology, Virology, Bacteriology – sciences all accelerated during

the 19th century• Discovery of Germ Theory; Pasteurization

– Advanced standards in nutrition, sterilization, overall health

• Food became widely available: goods in surplus, variety of dietary elements

• Thus, for 100 years, (primarily in the west) between 1750 (mid 18th century) and 1850 (mid 19th century), death rates declined by 50%, and birth rates remained constantly high.

• In 1750 ‘doubling time’ (number of years it takes to double the population) was 150 years

• In 1850, it had only taken 35 years to double the size of the population

• Dates vary between 1804-1820 as the year that the Earth’s population reached its first billion.– It took – literally – the beginning of human history until the 19th

century to accomplish this

• 1 billion in 1804• 2 billion in 1927 (123 years later)• 3 billion in 1960 (33 years later)• 4 billion in 1974 (14 years later)• 5 billion in 1987 (13 years later)• 6 billion in 1999 (12 years later)*

• *source: UNFPA http://www.unfpa.org/swp/swpmain.htm

Recap• The environment initially determined where people

could settle– As the physical landscape underwent changes (last

glaciation, for example) humans adapted to the new situations and began covering more space that they could inhabit

• With the advent of agriculture, human settlements came into being – stable, specific-location centers of social life

• Steady gains in technology were paralleled by gains in social conditions - disease could be prevented, studied, ‘controlled’

• Food was in ever greater abundance than before• The result was the precise ‘template’ of criteria

necessary to facilitate population growth

Human Mobility• Humans have always been in motion. All of our human history is

predicated on the human impulse of the “human being as adventurer”.

• More than 90 percent of human history, humans were hunter-gatherers– Method of subsistence that requires mobility

• This type of movement is called migration

• Human mobility is a spatial process

• Human movement accelerates the diffusion of ideas

• Human movement intensifies interaction across space and transforms entire areas

Why People Move• Many factors influence human mobility as a process – environmental change (as the traditional controller) – Availability of food (as the traditional controller)

• But also– Armed conflict – economic conditions – political conflict – cultural circumstances

• (linguistic, ethnic, religious conflict), – technological advances

• The more information we have about a destination, the easier we can obtain it, the easier we can move– Think about how the internet has impacted human mobility

• Direction and Distance are two key concepts in human migration

• Direction, (like location), is understood in two ways:

• Absolute distance:– Physical distance between two points (measured in kilometers or miles)– Can be read on a map– Does not change (typically)

• Relative distance:– Not linear in measurement but abstract

• Measured in terms of Cost or Time– These things mean different things to different people around the world

– Is subject to change• A new transportation method, or shorter route can impact how the distance to

something is perceived;– Four month’s journey; 2 months sea voyage; 6 hour plane ride; 2 hours by car

– Our perceptions of distance and direction are easily distorted; – Research shows ‘distance’ in particular affects how accurately

migrants perceive their destinations

Types of Mobility• There are three general patterns of movement:

• CYCLIC: When you go to daily classes or a job you engage in cyclic movement – movement with closed route

• PERIODIC: Temporary relocation– college abroad, military service, work transfer

• MIGRATORY: Human movement from source point to destination point without return– A society’s mobility is measured as the sum of cyclic,

periodic, and migratory movement of its population.

PatternsAll migration flows follow certain patterns. The most

prominent of these are:

• Rural-to-urban:– Movement in “steps”

• From a small community to a larger one , then to a larger one

• Repeated Relocation: – Migrants move after reaching end of first destination.

• May move several times before settling– Example: Early immigrants to America aimed to arrive in the US. Once they

reached the US (end of the destination), they re-located by moving West

• Counter (Return) Migration:– Leaving settlement point to either return to point of origin or

previous destination

Factors of Migration

• People move for a variety of reasons; typically it is a combination of what are called Push and Pull factors

• PUSH FACTORS: negative conditions; conditions that drive one away from a point of origin;

• PULL FACTORS: positive conditions; conditions that encourage one to move toward a point of destination

• Push factors are usually perceived more accurately – People more familiar with their own source location (home) than the

unknown place to which they are going to move– They therefore have a more positive, and realistic (usually) idea as to why

they should LEAVE– Push factors can be anything from personal considerations like work,

retirement, education, marriage to broader issues like weather and climate • (Earthquake prone; hurricane prone; drought prone; etc)

• Pull factors are usually perceived less accurately– Vague, abstract;

• Migrants do not have clear, first-hand experience or knowledge of the place they are moving to;

• Can have an exaggerated view of the “positive” elements associated with the place of destination, which can lead to expectations that may not be altogether realistic

The Luxury of Choice & the Fear of Compulsion

Two additional factors that influence migration are:

• The luxury of choice:– Being able to choose to migrate (voluntary)

• The fear of compulsion:– to be forced to move (involuntary/forced)

• European emigrants who took to the US in the 19th and 20th centuries were looking for opportunities – whatever poor living conditions some left behind, theirs was a (primarily) voluntary migration• Exception example:

• Irish Potato Famine

• The Transatlantic Slave Trade saw the forced migration of over 30 million Africans sold into slavery – Source region (Africa) and destination region (Americas, Caribbean)

were affected • In Greece’s history, the Population Exchange that followed WWI

and the destruction of Asia Minor was a forced migration of populations that resettled communities of Greek Orthodox and Muslims in Greece and Turkey, using religion as a ‘cultural’ criterion where language and ethnicity could not be easily determined.

• What other examples can you think of?

Terms• Emigrant: – individual who departs from a source location to

settle at a destination location• Ex: leaves one country to settle in another

– Departing

• Immigrant: – Individual who arrives and settles at destination

location from a source location • Ex: comes to new country to settle there

– Incoming

How did we get where we are?• The Genographic Project: • National Geographic, IBM, the WAITT Foundation all joined

forces in the one of the biggest scientific collaborations of all time; launched in 2005, the Genographic Project is a 5-year study tracking the DNA of over 300,000 people all over the world to find DNA patterns, links, and the ‘original’ human ancestor, and the rise of human populations out of East Africa more than 60,000 years ago.

• For an Atlas of Human History: – https://genographic.nationalgeographic.com/genographic/atlas.html

• For an Interactive Globe of Human Migration:– https://genographic.nationalgeographic.com/genographic/lan/en/globe.html