This term refers to the scientific study of human populations.
Demography
This number of births per woman is needed to replace a population.
2.1 (Will accept 2)
This type of land is used to grow crops and becomes scarce as populations grow.
Arable land
This term means the variety of life in a given area.
Biodiversity
Species that are likely to become extinct without immediate action are called this.
Endangered species
This major historical shift led to exponential human population growth.
This movement of people helps increase populations in developed countries.
Migration
In many underdeveloped countries, this resource is the primary fuel source for cooking.
Wood
This level of biodiversity refers to the variety of habitats and ecosystems.
Ecosystem diversity
This human activity has caused about 75% of current extinctions.
Habitat destruction
This population feature shows the distribution of ages within a population.
Age structure
When birth rates fall below replacement level, a population will eventually do this.
Decrease (decline)
This occurs when people move from rural areas to cities.
Urbanization
This type of diversity helps species survive disease and environmental change.
Genetic diversity
This type of species is not native to an area and often lacks natural predators.
Invasive or Exotic species
A population pyramid with more young people than old predicts this trend.
Population growth
During this stage of the demographic transition, death rates drop quickly while birth rates remain high.
Transitional Stage
This basic necessity often becomes unsafe when water supplies are contaminated by sewage.
Drinking water
A sharp reduction in population size that lowers genetic diversity is called this.
Bottleneck
These areas contain high numbers of endemic species and face severe threats.
Biodiversity hotspots
The book predicted the global human population would reach just over this number by 2025.
8 billion
This model explains how birth and death rates change as countries develop economically.
Demographic transition
Rapid population growth reduces this when resources such as food, water, and land are limited.
Standard of living
This human benefit of biodiversity involves travel to protected natural areas.
Ecotourism
This U.S. law protects endangered and threatened species and their habitats.
Endangered Species Act