Unit 3 Population Vocabulary

Age Structure

Structure of a population divided into groups by age.

Age Structure Diagram

A representation of the number of individuals in each age group in a population.

Baby Boom

The jump in birthrates in the years after World War Two, specifically between 1945 and about 1960, resulting in more than 65 million births.

Birth Rate

The rate at which births occur in a population, measured per unit of time relative to the population size.

Carrying Capacity

The maximum abundance of a population that can be maintained by an ecosystem without degrading its ability to support that abundance.

Crude Birth Rate

The annual number of live births per 1000 population, without regard to age or sex composition.

Crude Death Rate

The annual number of deaths per 1000 population, without regard to age or sex composition.

Death Rate

The rate at which deaths occur in a population, measured as the number of individuals dying per unit time.

Demographic Transition

The pattern of change in birth and death rates as a country transforms from undeveloped to developed.

Demography

The study of populations, especially their patterns in space and time.

Developed (less developed) Nations

A less developed nation is a nation with a low income average, a relatively backwards infrastructure and a poor human development index when compared to the global norm

Developed (more developed) Nations

A more developed nation is a nation that is technologically advanced and that enjoys a relatively high standard of living.

Doubling Time

The time necessary for a quantity to double.

Ecological Justification

An argument for conservation based on the specific functions that ecosystems provide for the persistence of life.

Emigration

The migration of people out of a country.

Exponential Growth

Growth where the rate of increase is a constant percentage of the current size.

Family Planning

Controlling reproduction and planning the timing of births.

Famine

A severe shortage of food.

Growth Rate

The net increase in some factor per unit time.

Immigration

The migration of people into a country.

Infant Mortality Rate

The probability of dying between birth and exactly one year of age, expressed per 1,000 live births.

J-Curve

A type of graph predicting the exponential growth of a population.

Kwashiorkor

Lack of sufficient protein in the diet leading to failure of neural development in infants.

Life Expectancy

The estimated average number of years an individual can expect to live.

Limiting Factor

The single requirement for growth available in the least supply in comparison to an organism's needs.

Linear Growth

Population growth modeled by adding a fixed amount each time period.

Logistic Growth Curve

The S-shaped growth curve generated by the logistic growth equation.

Malnutrition

The lack of specific components of food, such as proteins or vitamins.

Marasmus

Progressive emaciation caused by a lack of protein and calories.

Migration

The movement of individuals or populations from one habitat to another.

Moral Justification

An argument for conservation based on the intrinsic right of aspects of the environment to exist.

Mortality

A measure of deaths in a given population.

Overnutrition

Receiving more than enough calories to move or work.

Per Capita

Per person.

Population

A group of individuals of the same species living in the same area.

Population Dynamics

The study of changes in population sizes and the causes of these changes.

Population Momentum

The continued growth of a population that occurs after replacement level fertility is reached.

Replacement-Level Fertility

The fertility rate required for a population to maintain a constant size.

Survivorship Curve

Graphs showing a species' survival rate in a given ecosystem.

Type I Survivorship Curve

Curves representing species with a high survival rate of young, living out most of their expected lifespan.

Type II Survivorship Curve

Curves representing species with a relatively constant death rate throughout their life span.

Type III Survivorship Curve

Curves found in species that have many young, most of which die early in life.

The Rule of 70

A method to find the doubling time of a quantity growing at a given annual percentage rate.

Total Fertility Rate

The average number of children expected to be born to a woman during her lifetime.

Urban Sprawl

The unplanned expansion of development over a large area.

Utilitarian Justification

An argument for conservation based on the direct economic benefits provided by ecosystems.

Zero Population Growth

A population where the number of births equals the number of deaths, resulting in no net change.