Human Populations Flashcards
What 2 recent events have led to an explosion in the human population?
Development of agriculture and of manufacturing and trade that created the industrial revolution
What basic factors affect the growth and size of human populations?
Birth rate and Death rate
How else can individual populations be affected?
Migration
Define migration
When individuals move from one population to another
Define immigration
Where individuals join a population from outside
Define emigration
Where individuals leave a population
What is the equation for population growth?
(Births + Immigration) - (Deaths + Emigration)
What is the formula for calculating percentage population growth rate?
Population change during the period / Population at the start of the period x 100
What are birth rates affected by?
Economic conditions, Cultural and religious backgrounds, Social pressures, Birth control and Political factors
What is the equation for birth rate?
Number of births per year / Total population in the same year x 1000
What are death rates affected by?
Age profile, Food supply, Safe drinking water and effective sanitation, Medical care, Natural disasters and War
What is the equation for death rate?
Number of deaths per year / Total population in the same year x 1000
Define demographic transition
The transition from high birth and death rates to low birth and death rates as a country develops from a pre-industrial to an industrialised economic system
What is an age population pyramid?
A series of stacked bars representing the percentages of males and females in each age group
What is a survival curve?
A curve that plots the number of people alive as a function of time
