Evolution Vocab

artificial selection

The process by which humans select and breed specific organisms with desired traits.

fitness

most fit individuals pass on their genes

biogeography

study of geographic distribution of organisms

homologous structures

structural similarities in organisms that don’t have the same function

vestigial structures

remaining structures that no longer serve a purpose in the organism's current form but were useful to ancestors

genetic variation

differences in DNA among individuals within a population that contribute to diversity

gene pool

all copies of all alleles in a population

genetic drift

an event that decreases population size

bottleneck effect

reduction in a population due to a natural disaster

founder effect

few individuals colonize a new location

gene flow

populations gain or lose alleles when individuals move in or out of a population

prezygotic reproductive barriers

prevent successful reproduction between species before formation of a zygote

postzygotic reproductive barriers

prevent successful reproduction between organisms that occur after the formation of a zygote

biological species concept

a common way of defining a species

taxonomy

the science of classifying organisms into groups based on shared characteristics.

phylogeny

the evolutionary history and relationships among groups of organisms

selective mating

mates are carefully chosen

temporal isolation

species breed at different times

habitat isolation

behavioral isolation

specific behaviors are selected for

mechanical isolation

sex organs are not compatible

gametic isolation

gametes are not compatible

reduced hybrid viability

most hybrid offspring don’t survive

reduced hybrid fertility

hybrids are infertile

hybrid breakdown

first generation hybrids are fertile but their offspring is sterile

nomenclature

system for naming organisms

binomial nomenclature

species named by genus and species

clade

includes all related species and their common ancestor