APES - Chapter 5 Vocab

Species richness

The number of species in a given area.

Species evenness

The relative proportion of individuals within the different species of a location.

Phylogeny

The branching pattern of evolutionary relationships.

Evolution

A change in the genetic composition of a population over time.

Microevolution

Evolution below the species level.

Macroevolution

Evolution leading to the creation of new species and larger classifications of organisms.

Gene

Physical locations on chromosomes within each cell of an organism.

Genotype

The complete set of genes within an individual.

Phenotype

The actual set of traits expressed in that individual.

Mutation

An occasional mistake in the copying process, producing a random change in the genetic code.

Recombination

The process of chromosomes duplicating during reproductive cell division and a piece of one chromosome breaking off and attaching to another chromosomes.

Evolution by Artificial Selection

When humans determine which individuals to breed, typically with a preconceived set of traits in mind.

Evolution by Natural Selection

The environment determines which individuals survive and reproduce.

Fitness

The ability of an organism to survive in its environment.

Adaptation

Traits that improve an individual’s fitness.

Gene flow

The process by which individuals move from one population to another and thereby alter the genetic composition of both populations.

Genetic drift

A change in the genetic composition of a population over time as a result of random mating.

Bottleneck Effect

A drastic reduction in the size of a population that reduces genetic variation.

Extinction

An event that occurs when the last member of a species dies.

Founder effect

A change in the genetic composition of a population as a result of descending from a small number of colonizing individuals.

Geographic isolation

The physical separation of a group of individuals from others of the same species.

Allopatric speciation

The process of speciation that occurs with geographic isolation.

Reproductive isolation

Two populations of a species have evolved separately to the point that they can no longer interbreed and produce viable offspring.

Sympatric speciation

The evolution of one species into two species without geographic isolation.

Genetically Modified Organism (GMO)

The insertion of a desirable trait’s genes into other species of plants, animals, or microbes.

Range of Tolerance

The limits to the abiotic conditions a species can tolerate.

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 actuallh lives.

Distribution

The areas of the world in which a species lives.

Niche generalists

A species that can live under a very wide range of abiotic or biotic conditions.

Niche specialists

A species that is specialized to live under a very narrow range of conditions or feed on a small group of species.

Mass extinction

An event in which a large number of species goes extinct over a relatively short period of time.