population

Baby Boom: A period of significantly higher birth rates, especially in the U.S. from 1946 to 1964, following World War II.

Birth rate: The number of live births in a specific population over a set period, usually per 1,000 people per year.

Carrying Capacity: The maximum number of individuals an environment can support without damaging the ecosystem.

Crude Birth Rate: The number of live births per 1,000 people in a population per year.

Crude Death Rate: The number of deaths per 1,000 people in a population per year.

Demographic Transition Model: A theory that describes how birth and death rates change over time as a country develops, typically moving through four stages: high birth and death rates, declining death rates, declining birth rates, and low birth and death rates.

Demography: The study of populations, including their size, structure, distribution, and changes over time.

Density-dependent Factors: Environmental factors, like food and disease, that affect a population more strongly as its density increases.

Density-independent Factors: Environmental factors, like weather or natural disasters, that affect a population regardless of its size. 

Doubling Time: The time it takes for a population to double in size at a constant growth rate.

Emigration: The movement of individuals out of a population or area.

Exponential Growth: A population growth pattern where the size increases rapidly due to a constant growth rate.

Family Planning: Practices and methods used to control the number and timing of children born.

Growth Rate: The rate at which a population increases or decreases over time.

Immigration: The movement of individuals into a population or area.

Infant Mortality Rate: The number of infants who die before reaching one year old, per 1,000 live births.

IPAT model: A formula (Impact = Population × Affluence × Technology) used to estimate environmental impact based on population, affluence, and technology.

Replacement Level Fertility: The fertility rate needed for a population to replace itself without growing or shrinking, usually about 2.1 children per woman.

Survivorship Curves: Graphs showing the number or proportion of individuals surviving at each age for a species.

The Rule of 70: A formula used to estimate the doubling time of a population: 70 ÷ growth rate.

Total Fertility Rate (TFR): The average number of children a woman is expected to have during her lifetime.

Type I - Survivorship Curve: A curve showing high survival rates for most of the population until old age, common in species with few offspring (e.g., humans).

Type II - Survivorship Curve: A curve showing a constant death rate throughout the life of the organism, often seen in some birds and reptiles.

Type III - Survivorship Curve: A curve showing high mortality early in life, with a few individuals surviving to old age, common in species with many offspring (e.g., fish).