7 Evolution and Ecology Free Online FlashCards

What is evolution?

A change in the inherited characteristics of a population across generations, often measured by changes in allele frequencies.

What evolves: individuals or populations?

Selection acts on individuals, but evolutionary change occurs in populations across generations.

What does relative fitness measure?

Relative fitness is an individual's contribution of surviving offspring to the next generation.

What conditions allow natural selection to occur?

Heritable trait differences must affect survival or reproductive success for natural selection to occur.

What is an adaptation?

An adaptation is a heritable trait that improves survival or reproduction in a particular environment.

How do mutation and sexual reproduction contribute to variation?

Mutation introduces new alleles, while sexual reproduction reshuffles existing alleles.

What is genetic drift?

Genetic drift changes allele frequencies by chance and has especially strong effects in small populations.

What is gene flow?

Gene flow moves alleles between populations when individuals or their reproductive cells migrate.

What is speciation?

Speciation is the formation of new species, commonly as populations become reproductively isolated and diverge.

What initiates allopatric speciation?

Allopatric speciation begins when a geographic barrier separates populations and reduces gene flow.

What distinguishes sympatric speciation?

In sympatric speciation, reproductive isolation develops without geographic separation.

How can ecological differences promote speciation?

Populations using different food sources or breeding in different habitats may face different selection pressures and diverge.