Human Population Dynamics - Lecture 4 Overview

J-curve in population growth

A population growth form where the population undergoes exponential growth until it exceeds the carrying capacity, leading to a crash or dieback.

S-curve in population growth

A population growth form where the population density approaches an upper limit, the carrying capacity, resulting in a stable equilibrium between growth and environmental resistance.

Homeostatic controls in population growth

Self-regulating factors limiting population size, such as food availability, disease, and population density.

Biotic potential

The maximum growth rate a population can achieve in an unlimited environment, though it is never fully realized.

Demographic transition model

A model used to analyze changes in birth and death rates as countries industrialize, leading to population stabilization.

Key features of the demographic transition model

It includes stages where birth and death rates fall, leading to lower population growth after an initial boom.

Population carrying capacity

The maximum number of individuals an environment can sustainably support.

Projected world population for 2100

10.9 billion.

Birth and death rates

Birth rate: live births per 1000 people per year. Death rate: deaths per 1000 people per year.

Industrial Revolution impact on population growth

It led to a decrease in death rates due to improved food supply, medical knowledge, and sanitation, causing population growth.

Global graying

The aging of populations in developed countries, leading to economic challenges as the ratio of workers to retirees decreases.

Population pyramids and age structure

They show the distribution of age groups, indicating whether a population is young, old, or balanced.

Total fertility rate (TFR)

The average number of live births per woman, which has declined globally from 5 in 1955 to 2.2 in 2024.

Regions with highest birth rates in 2024

Sub-Saharan and Central Africa.

Fragile states

Nations with high birth rates, high youth populations, and increased risk of civil unrest due to population pressures.

Significance of an aging population

It places pressure on retirement systems and reduces the workforce supporting the elderly, as seen in many European countries.

Russia's population change since 1994

Russia's population declined due to a drop in birth rates and an uptick in death rates from 149 million in 1994 to 145.6 million in 2022.

Population growth rate

The rate at which a population increases or decreases, measured as a percentage based on birth and death rates.

Factors affecting a population's carrying capacity

Availability of resources, disease, and environmental conditions.

Under-5 mortality and its change

Under-5 mortality has steadily decreased worldwide since 1950 and is expected to continue declining through 2100.