1. Mitchell McGovern Sarah Mason Jessie Fedyke
Population
Mitchell McGovern
Sarah Mason
Jessie Fedyke

2. Importance of Population
Studying populations allows us to see where people are found across Earth’s surface.
It also allows us to see the areas where population is growing too fast/ too slow.
Demography: the study of the characteristics of human populations
Population is measured by a Census, a count of the number of people in a given area, usually every ten years. Very important to determine government funding.

3. Declining Rate of Natural Increase
NIR: -% a population grows each year
-CDR-CBR=NIR
CDR: -Total # of deaths in a year for every 1,000 people
CBR: -Total # of live births in a year for every 1,000 people
Doubling Time -# of years needed to double a population
World NIR is decreasing (as of 1963)
Causes: -Sterilization, especially in India
-Increase in Education -Family Planning -Lower birth rates improve economic conditions -propaganda now encourages small families (china)
*Exception: LDC -Almost all the world population growth is from LDC’s (95% of World NIR)

4. Measures of population
Total Fertility Rate: -measures the # of births in society, average # of children a woman will have during childbearing years of
World TFR is 2.6 children per woman -LDC’s TFR is high -MDC’s TFR is low
Infant Mortality Rate -# of deaths of infants under the age of 1, per year -LDC’s IMR is high -MDC’s IMR is low
Life Expectancy -Average # of years a newborn infant can expect to live at current mortality levels -High in MDC’s -Low in LDC’s
Dependency ratio -# of people too old or young to work compared to the # of their working years -High levels of YOUNG dependent people in LDc’s -High levels of OLD dependent people in MDC’s

5. World Population Distribution
7 billion
Factors of distribution: -Climate and Weather, availability/quality of water, topography, arable land, along with political and economic factors
Culture/ethnicity
Areas of high political instability are undergoing changes in population
Population growth curves: -S curve; historical growth -J curve; exponential growth

6. Population distribution
Ecumene -Portion of the earth’s surface occupied by permanent settlement -today 3/4ths of the world population lives on only 5% of earth’s surface
20% of earth’s surface is not arable due to dry lands and large deserts, low population in these areas
In areas of high rainfall with more than 50 inches per year the soil is depleted of nutrients therefore the population is low
Near the North and South poles with massive elevations and ice coverage very little humans or animals live.
Country:
Population
China
1,354,040,000
India
1,210,193,422
United States
315,761,000
Indonesia
237,641,326

7. Density
Population Density -numerical measure of the relationship between the number of people and some other unit expressed as a ratio - helps geographers describe distribution of people in comparison to available resources.
Arithmetic Density -Total # of objects in an area -To find it you take the total # of people divided by total land area -Does not always accurately portray population distribution because in some countries a large majority of the people live in a certain part, they are not spread out evenly.
Physiological Density -# of people per area of arable land in a region
Agricultural Density -ratio of farmers to the amount of arable land -measures economic differences
Why? -Comparing agricultural and physiological densities allows you to see the relationship between population and resources

8. World population threats
Epidemiologic transition: -Focuses on distinctive causes of death in each stage of the demographic transition
Epidemiology: -branch of medical science concerned with the incidence, distribution, and control of diseases that affect large numbers of people

9. Epidemiologic transition
Stage 1, Pestilence and Famine ex. Black Plague -spread from urban areas to rural areas wiping out entire villages, thought to originate from the Tatar army.
Stage 2, Receding Pandemics occuring over a wide geographic area. ex. -Edwin Chadwick ( ) said that residents in poorer neighborhoods had higher incidences of pandemic diseases -Dr. John Snow ( ) said that the contaminated water was the cause of death, not sinful behavior.
Stage 3, Degenerative and human-created diseases. Ex. Cancer -End of deaths from infectious illnesses due to vaccines
Stage 4, delayed degenerative diseases ex. Stage 3 diseases still linger but there are new treatments to extend life expectancy. -Result of more research in medicine and reduced use of drugs.
Stage 5, Stage of reemergence of infectious diseases and parasitic disease ex. Malaria -Stage is more of a theory, thought to might happen due to evolution with microbes evolving and changing vaccines may stop working, like building up immunity to certain medicine from so much use.

10. Malthus Theory
Thomas Malthus predicted that population was growing too fast that eventually we would run out of food. -With an increase in population resources would deplete and disease, famine, and war would ensue. -population grows geometrically while population growths arithmetically
Reasons he was wrong
Malthus failed to anticipate that poor countries would have rapid population growth
Theory based on his idea that food and resources were at a fixed amount.
Malthus’s arithmetic theory didn’t take into account that too few people could also slow the economy just as overpopulation might
Food production increased with green revolution -fertilizer -Genetically enhanced food -technology

11. Demorgaphic Transition Model
Stage 1: Low Growth, high birth AND death rates -Hunting and Gathering, no modern medicine, no country is still in stage one today
Stage 2: Death rate drops, but birth rate stays high -Occurred in MDC’s during the 18th with most LDC’s during mid 19th century due to the industrial revolution, improved sanitation/medicine/technology
Stage 3:Birth rate drops, death rate low -CBR is still higher than CDR, most MDC’s went through stage 3 during the early 1900’s with a sudden drop of birth rates with rural families moving to cities no longer needing several kids to work farms
Stage 4: Low growth overall -Countries enter stage 4 when there is zero population growth, or negative growth (communist rule) -BR = DR or zero population growth -most of Europe and the U.S. have zero NIR
Stage 5: When the crude death rate is higher than the birth rate -no countries have undergone stage 5 yet

12. Population Pyramids
Population Pyramid: bar graph that displays age and gender of a population with males on the left and females on right, determined by CBR -broken down into 5 year age groups -Sex ratio: # of males per hundred females

13. Helpful review links