AP Environmental Science Unit 2 Vocab By.Abrielle Walker

Adaptation

A trait that improves an individual's fitness

Allopatric speciation

The process of speciation that occurs with geographic isolation

Aquaculture

The farming of fish, shellfish, and seaweed

Climax community

Historically described as the final stage of succession

Ecological succession

The predictable replacement of one group of species by another group of species over time

Ecological tolerance

The suite of abiotic conditions under which a species can survive, grow, and reproduce. Also known as the fundamental niche

Ecosystem diversity

The variety of ecosystems that exist in a given region

Ecosystem services

The processes by which life-supporting resources such as clean water, timber, fisheries, and agricultural crops are produced

Episodic disruption

Occurring somewhat regularly, such as cycles of high rain and low rain that occur every 5 to 10 years

Evolution

A change in the genetic composition of a population over time

Evolution by artificial selection

when humans determine which individuals breed, typically with a preconceived set of traits in mind

Evolution by natural selection

The process in which the environment determines which individuals survive and reproduce

Evolution by random processes

The processes that alter the genetic composition of a population over time, but the changes are not related to differences in fitness among individuals

Fitness

An individual's ability to survive and reproduce

Generalists

Species that can live under a wide range of biotic or abiotic conditions

Genetic diversity

A measure of the genetic variation among individuals in a population

Genetically modified organism (GMO)

An organism produced by copying genes from a species with some desirable trait and inserting them into other species of plants, animals, or microbes

Geographic range

Areas of the world in which a species lives

Habitat diversity

The variety of habitats that exist in a given ecosystem

Indicator species

A species that demonstrates a particular characteristic of an ecosystem

Intermediate disturbance hypothesis

The hypothesis that ecosystems experiencing intermediate levels of disturbance will favor a higher level of diversity of species than those with high or low disturbance levels

Island biogeography

The study of how species are distributed and interacting on islands

Keystone species

A species that is not very abundant but has large effects on an ecological community

Macroevolution

Evolution that gives rise to new species, genera, families, classes, or phyla

Mass extinction

A large number of species that went extinct over a relatively short period of time

Microevolution

Evolution at the population level

Periodic disruption

Occurring regularly, such as the cycles of day and night or the daily and nightly cycle of the moon's effects on ocean tides

Pioneer species

In primary succession, species that can survive with little to no soil

Population bottleneck

When a large population declines in number, the amount of genetic diversity carried by the surviving individuals is greatly reduced

Primary succession

Ecological succession occurring on surfaces with bare rock and no soil

Provision

A good produced by an ecosystem that humans can use directly

Random disruption

Occurring with no regular pattern such as volcanic eruptions or hurricanes

Realized niche

The range of abiotic and biotic conditions under which a species actually lives

Resilience

The rate at which an ecosystem returns to its original state after a disruption

Resistance

In an ecosystem, a measure of how much a disruption can affect flows of energy and matter

Secondary succession

The succession of plant life that occurs in areas that have been disturbed but have not lost their soil

Specialists

Species that only live under a narrow range of biotic or abiotic conditions

Species-area curve

A description of how the number of species on an island increases with the area of the island

Species diversity

The number of species in a region or in a particular ecosystem

Species evenness

The relative proportion of individuals within the different species in a given area

Species richness

The number of different species in a given area

Sympatric speciation

The evolution of one species into two, without geographic isolation