AP Biology Unit 7: Evolution

A list of selected terms on Unit 7 taken from the 2020 Princeton Review book for AP Biology.

evolution

the change in a population over time

natural selection

the driving force of evolution that operates on the level of the individual

paleontology

the study of fossils

biogeography

the study of the distribution of flora and fauna in the environment

embryology

the study of development of an organism

comparative anatomy

the study of the anatomy of various animals

homologous structures

features in different species that are structurally similar but have different functions; indicates common ancestry

analogous structures

features in different species that are structurally different but have similar functions; indicates convergent evolution

molecular biology

the study of life at the molecular level; most compelling proof of evolution

common ancestor

the shared ancestor of different species that arose from one population

phylogenetic tree

a branching or tree diagram that displays the evolutionary relationships among species based on their similarities and differences

cladogram

a branching or tree diagram that shows relations among organisms using even spacing

out-group

the least related species compared to other species

genetic variability

the genetic differences in each individual of a population

random mutation

a genetic variation that occurs spontaneous

adaptation

a variation favored by natural selection

evolutionary fitness

the ability of an individual to survive and reproduce to pass on traits

sexual selection

natural selection in which mates are selected for certain characteristics

genetic drift

a change in the genetics of a population not due to natural selection

bottleneck effect

a change in allele frequency following a reduction in population size

founder effect

a change in allele frequency following the migration of a subgroup of a population

gene flow

the movement of alleles from one population to another

directional selection

natural selection that favors one extreme of a phenotypic distribution

stabilizing selection

natural selection that favors the median of a phenotypic distribution

disruptive selection

natural selection that favors both extremes of a phenotypic distribution

species

a population whose individuals can breed to produce viable offspring

reproductive isolation

mechanisms that prevent breeding between different species

divergent evolution

speciation that occurs when two populations experience different environmental pressures and undergo different variation

punctuated equilibrium

divergent evolution that occurs quickly after a period of stasis, often due to a major event

adaptive radiation

speciation that occurs due to an abundance of available ecological niches

pre-zygotic barrier

a mechanism that prevent fertilization

post-zygotic barrier

a mechanism that prevents viable offspring to be produced from a hybrid organism

convergent evolution

the appearance of similar, analogous traits between two unrelated species due to exposure to similar selective pressures

allopatric speciation

speciation that results from a geographic barrier that prevents interbreeding between two populations

sympiatric speciation

speciation that results without a geographic barrier

polyploidy

potential speciation occurring when plants get doubles of their chromosomes (example of sympiatric speciation)

Hardy-Weinberg equilibrium

the state of a population in which allele and genotype frequencies will remain constant