Population Structure, Movements and Concentration

SociologySociology

Population Structure, Movements and ConcentrationBy Kathy S. Stoley

Topics to be coveredPopulation Population Change

Sources of population change Birth Rate Death Rate Migration Rate and its types

Population Structures Population Pyramids

Population

“A population is all the organisms that belong to the same group or species and live in the

same geographical area.”

Demography

“Demography is the study of human population.”

(Demo= population Graphy=measurement )

Top 10 populous countries of the world

Population change

Definition : “The difference between the size of the

population at the end and the beginning of a period.”

First Sources of population change

Birth rate“The reproductive performance indicated by the incidence of childbearing in a population

is called Birth Rate.”

Crude Birth rate “The number of live births in a year per 1000

people in a population is called Crude Birth rate.”

Age specific fertility rates“The number of births to women in certain

age groups in a population.”

Second source of population change

Mortality “The incidence of deaths is called mortality.”Crude death rate “The number of deaths in a year per 1000

people in a population.”

Age specific mortality rate “

“The number of deaths per age group in a population.”

Events that impact death rateWar Genocide

How to reduce death rateBy improving public healthBy raising economic status of an area

Third source Of Population change

Migration “The movement of people into and out of a

specific area.” It includes both immigration and emigrationImmigration means the movement of people

into the area.Emigration means the movement of people out

of an area.

Migration Rate

Migration rate “The change per 1000 people in a population

of an area in a given year.”

Types of Migration

Voluntary migration

“Voluntary migration is the movement of people into a new region by their own choice. People will migrate generally

because the new place has “pull factors” that motivated their movement.”

Involuntary/Forced migration

“Forced migration is the movement of people into a new region for reasons other than

their own choice. The migration is set into motion because of “push factors” forcing

people to move.”

Mass Migration

“Mass migration is when large number of people move at one time and it is more often

involuntary than voluntary.”

Population structure

Population pyramids depict the population composition of a country.

Also known as “Age sex pyramids”Because they show the population not only by

age but also by the relative proportion of men and women in each age group.

Population growth

“An increase in the number of people that reside in a country, state or city.”

Population Pyramids

What is Population Pyramid?It is a diagram that gives information

about the proportion of males and females in each age group.

Also shows:- proportion of young people (0 -14 )- proportion of working people (15 – 59)- proportion of elderly people (60+)

Types of Population Pyramids

Triangular-shapedBeehive-shaped Pyramid Rectangular-shaped Pyramid Shape of pyramids is controlled by

– births,– deaths, &– migrations.

Triangular Shaped Pyramid

Fast Population GrowthBroad base. Low proportion of older people. A steady upwards narrowing shows that more

people die at each higher age band.This type of pyramid indicates a population in

which there is a high birth rate, a high death rate and a short life expectancy.

Example

NigeriaLocated in Western Africa, the Federal

Republic of Nigeria (named for the Niger River) is the most populous country of Africa. 

Annual growth rate in 2000 was 2.7%Median age for female was 17.6 years old.

Beehive Shaped Pyramid

Slow Population GrowthNarrow BaseLarge proportion of working population,

15-59 year old - large group of economically active population

Low Birth Rates

Example

United StatesAnnual Growth Rate in 2000 was 0.9%Median age for female was 36.8 years old.

United States 2000

Rectangular Shaped Pyramid

Declining Population GrowthZero Pop GrowthNarrow Base Low Birth RatesLife-expectancy is high e.g. 80+Low death rates

Example

UkraineAnnual Growth Rate in 2000 was -0.6%Median age for female was 39 years old

Ukraine 2000

T. Robert Malthus(1766 - 1834)

Principle Of PopulationPrinciple Of Population"Population, when unchecked, increases at a geometrical ratio. Subsistence increases only in an arithmetical ratio. Slight acquaintance with numbers will show the immensity of the first power incomparison with the second."

“Population must always be kept down to the level of the means of subsistence.”

“Malthus was the first to inquire into “the means by which this level is effected.”

Man has no natural predators (savefor other men). "The passion between the sexes hasappeared in every age to be so nearly the

same, that it may always be considered, in algebraic language as a given quantity.“

Population, when unchecked, willdouble itself every twenty-five years.

"...Supposing the present populationequal to a thousand million, the human species

would increase as the numbers 1, 2, 4, 8,16, 32, 64, 128, 256, and subsistence as 1, 2, 3, 4, 5, 6, 7, 8, 9...

• "In two centuries the population would be to the means of subsistence as 256 to 9; in three centuries as 4096 to 13, and in two years the difference would be almost incalculable.”

SubsistenceSubsistence"In this supposition no limits

whatever are placed on the produce of the earth….

“It may increase for ever, and be greater than any assignable quantity; yet the power of population being in every period so much superior….

Law of Necessity:Law of Necessity:• "The human species can only be

kept down to the level of the means of subsistence by the constant operation of the strong law of necessity, acting as a check upon the greater power."

Positive Checks Positive Checks "The positive checks to population are extremely various, and include every cause whether arising from vice or misery, which in any degree contributes to shorten the natural duration of human life.“ “Under this head therefore may be enumerated all unwholesome occupation, severe labor and exposure to the season, extreme poverty...

• “Bad nursing of children, excesses of all kinds, the whole train of common diseases and epidemics, wars, pestilence, plague and famine”.

WarFamineDisease Infanticide

Preventive ChecksPreventive ChecksPreventive checks aimed at reducing

birth rate by (1) Marrying at later age(2) Abstinence from sex outside marriage(3) Birth ControlIn Malthus’ view, birth control led to vice.Still, he maintained, it is the least evil actthat can control population

Food and PopulationFood and Population• This was Malthus “principle of population,”

which is basically the law of supply and demand applied to the relationships between food production and population growth. As the food supply increases, food becomes cheaper, and more children are brought into the world. As there are more mouths to feed, food becomes more expensive, thus causing more land to be put under the plow, or greater investment in fertilizer.

The PoorThe Poor Consistent with his functionalist orientation, Malthus

asserts that a working class is absolutely essential toevery society. Labor will always be necessary to wrest subsistence

from nature. The institution of private property and self-interest

provide the motivation for human thought and action.

It is the goad of necessity, the desire to avoid poverty or to obtain riches that motivates much of human industry.

Welfare ReformWelfare ReformThis analysis of welfare does not leadMalthus to advocate that the poor shouldbe left to their plight.Rather, he suggests some institutional

reforms--consistent with the law of population--that will serve to make a more just, equitable society.

Malthus’ EvolutionarySystem: Eight major

points1)population level is severely limited by subsistence2) when the means of subsistence increases, population increases3) population pressures stimulate increases in productivity4) increases in productivity stimulates further population growth5) since this productivity can never keep up with the potential of population growth for long, there must be strong checks on population to keep it in line with carrying capacity.

• 6) it is through individual cost/benefit decisions regarding sex, work, and

• children that population and production are expanded or contracted.

• 7) positive checks will come into operation as population exceeds subsistence level.

• 8) The nature of these checks will have significant effect on the rest of the sociocultural system--Malthus points to misery, vice, and poverty.

CriticismCriticismMalthus’s prediction did not come true because He presented his theory in an era marked by high population growth and restricted farmland He did not foresee the technological advancements in agriculture and contraception.

The Demographic Transition

DEMOGRAPHIC TRANSITION MODEL:

• The Demographic Transition Model is a geographical model used to explain the processor of change from high birth rates and high death rates to low birth rates and low death rates apart of the economic development of a country from a pre-industrial to an industrialized economy.

Introduction• Demographic Transition Model (DTM)

Represents a nation’s transition through industrialization Commonly involves 4 stages An idealized picture of population change in a country.

Criticism:A variety of factors influence population trend that do not fit this theory Thus Due to advances in public health (e.g., sanitation, vaccines), other countries are experiencing improved health without a corresponding period of industrialization, resulting in High Birth and low death Population growth

Population and Urbanization

• Population:- A population is a summation of all

the organism of the same group or species, which live in the same geographical area, and have the capability of interbreeding.

• Urbanization:- Urbanization is a population shift from rural to

urban areas, and the ways in which society adapts to the change.

Urban Area

• An urban area is a location characterized by high human population density vast human-built features Urban lifestyles are generally considered more “modern” and faster paced than non-urban lifestyles.

Rural area:- In general, a rural area is a geographic area that is located outside cities and towns. Rural areas are typically considered to have a more traditional and slower-pacedlifestyle.

• Total U.S. Population and Percentage Urban, Selected Years 1930–2000.

Sources: U.S. Census Bureau “Population: 1790 to 1990” and U.S. Census Bureau 2001a.

History of Urban SociologyFour Largest U.S. Cities and Other Urban

Places, Selected Years 1790–2000

History of Urban Sociology

The Chicago-school sociologists produced several ethnographies of the

urban life of Chicago residents, including studies of gangs, transients, and immigrants (Savage and Warde 1993). A 1938 piece by Louis Wirth (1897–1952) describing an urban lifestyle has been called “one of the most influential sociological articles ever written” (Savage and Warde 1993, 97). It is also reputed to be the article “most widely cited in sociology” (Abercrombie, Hill, and Turner 2000, 370). In his article, Wirth discussed differences

between social interaction and life in cities and rural areas, focusing on isolation and loss of individuality. His argument was

that cities change social relationships for the worse. Whether this is actually the case has been examined in a variety of

subsequent studies.

Urban EcologyUrban ecology is the scientific

study of the relation of living organisms with each other and their

surroundings in the context of an urban environment. Urban ecology focuses on the interaction between

human population and the environment, including both material and nonmaterial aspects of human

culture.

Concentric zone modelThe Concentric zone model, also known as the Burgess model or the CCD model, is one of the earliest theoretical models to explain urban social structures. It was created by sociologist Ernest Burgess in 1923.

Sector modelThe sector model, also known as the Hoyt model, is a model of urban land use proposed in 1939 by economist Homer Hoyt. It is a modification of the concentric zone model of city development. The benefits of the application of this model include the fact it allows for an outward progression of growth.

Multiple nuclei modelThe multiple nuclei model is an economical model created by Chauncy Harris and Edward Ullman in the 1945 article

"The Nature of Cities"

URBAN SOCIOLOGY TODAY

First century of urban sociology

Cont’dCurrent urban sociology

Political Economy Perspective

Focus on the inter-relationship between political and economic forces

Draws from the conflict perspective of “Karl Marks”

Sociospatial Model

Views local areas as comprised of various, often competing, growth networks rather than a single coalition.

The process of population moving out of central cities to surrounding areasSuburbs: urban areas out of city boundaries.

Counter policies• Urban Renewal: Government-

funded programs that aim to rejuvenate cities.

Cont’d• Gentrification: Affluent buy run-

down properties at low cost and upscale them.

• Increases the property value.