Biodiversity
Refers to the variety of species, the genes they contain, and the ecosystems they live in.
Natural capital
Examples include food, fuel wood, energy, and medicines.
Species richness
The number of species in a given area.
Species evenness
The relative proportion of different species in a given area.
Mutation
Random changes in the DNA of a cell.
Genetic diversity
Variability in the genetic makeup among individuals within a single species.
Natural selection
Results in a population that contains a greater proportion of organisms better adapted to certain environmental decisions.
Fitness
An organism's ability to survive and reproduce.
Adaptation
Traits that improve an individual's fitness.
Geographic isolation
When geologic or climatic events separate populations.
Reproductive isolation
An inability to pass new traits between separated populations.
Speciation
The formation of 2 species from one because of divergent natural selection in response to changes in environmental conditions.
Extinction
When an entire species disappears from Earth.
Background extinction
Normal extinction of various species.
Mass extinction
A significant rise in extinction rates above the background level.
Range of tolerance
Determines whether an organism is living in its fundamental or realized niche.
Fundamental niche
The suite of abiotic conditions under which a species can survive, grow, and reproduce.
Realized niche
The range of abiotic and biotic conditions under which a species actually lives.
Generalist species
A type of species with a broad niche since it can eat a variety of food.
Specialist species
A type of species with a narrow niche who eats from one food source.
Native species
A type of species that lives and flourishes in a particular environment.
Invasive species
A nonnative species introduced to a new environment.
Keystone species
Its disappearance has a large impact on the community.
Indicator species
A species that provides an early warning that damage to an ecosystem is occurring.