XI - Human Population:Growth, Demography, & Carrying Capacity Flashcards
Population chance is calculated as
the difference between individuals entering and leaving a population
Birth rate
reported as the number of births per thousand people
Death rate
reported as the number of deaths per thousand people
Zero population growth
occurs when factors that increase and decrease population size balance
Rule of 70
number of years it takes for an amount growing at x % per year to double is roughly equal to 70/x.
Developed countries tend to have
lower birth rates & death rates than developing countries
World’s most populous nations
China India USA Indonesia Pakistan Brazil Nigeria Bangladesh Russia Mexico
Population size by region
Asia 4.6 B Africa 1.3 B Europe 0.75 B Latin America 0.65 B North America 0.37 B Oceania 43 M
Average total fertility nowadays
2.5 children per woman
How has the total fertility in the United States behaved?
Major increase during “baby boom”
Now hovering below replacement level at 1.8 births per woman
What are significant factors that decrease human fertility levels?
increase in average level of education & affluence;
decrease in importance of child labor;
increased urbanization;
increased cost of raising & educating children;
increased educational & employment opportunities for women;
decreased infant mortality;
higher average age of marriage;
greater availability of private & public pensions;
greater availability of reliable birth control;
greater availability of legal abortions;
change in religious beliefs, traditions, & cultural norms away from encouraging large families.
Birth control method
abstinence sterilization hormonal implant IUD Vaginal pouch Condom Spermicide Cervical cap
Infant death rates are lower in
developed countries than developing countries.
The rapid growth in the world’s population has not resulted from
an increase in birth rates, but rather a major decrease in death rates.
What primarily has caused the exponential growth in human?
Increasing difference between birth & death rates
In developed countries decreases in death rates are being accompanied by
decreases in birth rates over time.
Rate of natural increase is equivalent to
crude birth rate minus crude death rate
In developing countries decreases in death rates have not been accompanied by a
s large of decreases in birth rates over time, leading to major population increase.
Age structure
refers to the proportion of the population in each age class
prereproductive
0–14 years