AP®︎ Environmental Science: Topic 2.1 Flashcards

The variety of life in a defined area, including genetic, species, and habitat diversity

Variation in genes, alleles, and inherited traits within a population or species; greater variation increases the likelihood that some individuals can tolerate environmental stress

A sharp population decline that leaves a limited sample of the original alleles, reducing genetic diversity even if abundance later recovers

Variation among species in a community, determined by both species richness and species evenness

The number of different species found in a defined area, regardless of each species’ abundance

How equally individuals are distributed among the species present in a community

1 − D = 1 − [Σ nᵢ(nᵢ − 1)]/[N(N − 1)]; it is the probability that two individuals selected without replacement belong to different species, with values nearer 1 indicating greater diversity

The variety of habitats within a geographic area; more habitat types generally support species with a wider range of ecological requirements

A change that makes an area unable to provide organisms’ required conditions or resources, tending to eliminate specialists first, then generalists, and to reduce species needing large territories

A species that uses a narrow range of resources or environmental conditions and is therefore especially vulnerable to habitat loss

A species that can use a broad range of resources or conditions, allowing it to persist longer than specialists as habitat is lost

The disappearance of a species from one area while it continues to survive elsewhere

An ecosystem’s ability to remain relatively unchanged when a disruption occurs; greater biodiversity generally increases this ability

An ecosystem’s ability to recover toward its prior structure and function after a disruption; greater species diversity generally increases this ability

A numerical measure that combines species richness and relative abundance to compare community diversity