Population Movement
Fertility and mortality are two elements of the demographic equation.
The third element is migration, the movement of people into or out of a
given place. Migration may take people across national political boundaries
in response to deteriorating political, economic, or environmental conditions;
or it may only involve movement within the country. It may also be involuntary
or voluntary. Immigrant populations whose cultures, languages, and religions
have blended to form new national identities have profoundly influenced
a few countries, including the United States, Canada, and Australia. The
large numbers affecting selected countries notwithstanding, international
migrants account for only about 2% of the worldís population, about 125
million people, and have little impact on population change in most
countries.
Some international migrants are forced to leave their home countries due to war or unstable political circumstances. For example, according to the United Nations High Commission for Refugees, almost 1.5 million refugees from Afghanistan were living in Iran in 1997, and another 1.2 million in Pakistan . In 1999 almost 11.5 million people were recognized as refugees, with most living in the Middle East, Africa, and Europe. In addition, another 6.7 million people were recognized as "internally displaced persons" .
Not all international migrants are refugees, however. Many move in search of employment and a better standard of living. About half of all international migrants move from one developing country to another. For example, large numbers of men, many of them from such countries as Egypt, South Korea, Philippines, Thailand, and Pakistan, have moved as guest workers to the oil-rich countries of the Persian Gulf region to take advantage of a job surplus in this area. In many cases, immigrant labor makes up a large share of the labor force and skews the population age structure. For example, in the United Arab Emirates, immigrants made up 90% of the labor force in 1995 . Other international migrants flock to more developed countries, filling jobs left vacant by aging and affluent populations. About one-third of the worldís migrant population lives in Germany, France, United Kingdom, United States, Italy, Japan, and Canada. For example, migrants from North Africa and Turkey have located in France and Germany, respectively, in the late 20th century. Use of the gravity model aids in the analysis of contemporary migration patterns and affords students the opportunity to test such concepts as distance decay, friction of distance, and intervening opportunity, as they relate to migration decisions.
The United States is also a popular target for migrants seeking employment and education opportunities. For example, in 1997 there were an estimated 25.8 million foreign-born residents in the United States, or 9.7% of the total population. Nearly half of all foreign-born are of Hispanic origin. The single largest group of foreign-born is from Mexico, accounting for almost 30% of all immigrants, followed by persons born in the Philippines, Canada, China, Cuba, Dominican Republic, El Salvador, Jamaica, Korea, Germany, United Kingdom, and Poland. In addition to the introduction of greater racial and ethnic diversity into the American population, immigrants may also have some effect on the age structure of the U.S. population. The majority of immigrants tend to be young adults with their families, which may hold down the median age of foreign-born populations somewhat; however, little if any effect is projected for the population as a whole. The Census Bureau projects that the median age in the United States will rise to 38.1 years by 2050, from the current 34.3 years. Foreign-born populations, while found in every state, have gravitated toward certain gateway states, especially California with more than 7.7 million foreign-born residents and New York with 3.0 million foreign-born residents .
Migration also occurs within countries. In many less developed countries, just as in the case of international migration, internal migrants are often fleeing civil disturbances or failing economic conditions, as noted before. Rural to urban migration involves the movement of literally tens of thousands of people to large metropolitan areas, adding to the problems of already burgeoning cities with over-taxed utilities and services. In more developed countries, the trend is just the reverse, with people abandoning crowded central cities in favor of suburbs and the rapidly transforming rural fringe beyond. In the United States, for example, this process is evident in declining populations of central cities within growing metropolitan areas, such as Washington, DC, where the city itself experienced a net decline of 10.6% in population between 1990 and 1996, while the metropolitan area saw a net increase of 8.1% over the same period .
On a different scale, the United States has experienced an internal shift in population from states in the Northeast and Midwest to states in the South and West--the region referred to as the Sunbelt. In 1960, 54% of the U.S. population lived in the Northeast and Midwest, but by 1995 only 43% of the population lived in these two regions. Attracted by employment opportunities and a lower cost of living, people have flocked to the Sunbelt states of Nevada, Arizona, Colorado, Utah, and New Mexico, as well as to Idaho and Washington in the West, and to Georgia in the South, all of which experienced annual growth of 2% or above between 1990 and 1995. This trend in population movement is not only changing the demographic profile of the country and the states most involved, it is also introducing change in the cultural, political, and economic fabric of both the regions losing and those gaining population.
Regardless of where students live, migration, either international or internal, is likely to have left its mark on the local area, whether by the presence of an immigrant population or by the relocation of jobs and the associated movement of labor. Local or personal experience can be the springboard for studying migration on a larger scale. For example, students can trace their own immigrant roots and compare them to major national trends. Or they can look for and analyze immigrant imprints, such as architectural style, place names, churches, and restaurants in the local cultural landscape.
Short-Term, Local Movements, and Activity Space
While advanced placement students must frequently rely on data sets
collected by governments and international agencies as they examine many
aspects of population, short-term mobility and activity space fall within
the realm of local investigation. Short-term movement and activity space
involve, for example, daily trips to and from school or work, vacations,
and temporary relocation of students attending college away from home.
Activity space is directly related to age, in that as children get older
they are likely to have greater independence to travel farther and farther
from home, if only to attend school or to meet friends at the mall. Students
can conduct interviews with people of different ages concerning their local
mobility patterns. The results can be mapped and graphed to facilitate
analysis and formulation of generalizations about mobility based on questions
such as: How is activity space affected by age? How is activity space
limited by perceptions of danger? How does activity space vary between
weekdays and weekends? How does activity space relate to distance
decay models, i.e., how is the purpose of a trip related to the distance
one is willing to travel? Generalizations formed at the local level
can then be applied to the movement of people at other scales, state, national,
or global.
