Key Terms
This term describes the differential survival and reproduction of individuals due to differences in phenotype.
What is natural selection?
The book in which Darwin published his theory of evolution by natural selection.
What is “On the Origin of Species”?
Structures that are similar because of common ancestry, such as the limb bones of vertebrates.
What are homologous structures?
The type of speciation that occurs without geographic separation.
What is sympatric speciation?
The selection process where individuals with extreme phenotypes have an advantage.
What is directional selection?
The process by which organisms better adapted to their environment tend to survive and produce more offspring.
What is adaptation.
The group of islands where Darwin made significant observations that contributed to his theory.
What are the Galápagos Islands?
Structures that have no apparent function and appear to be residual parts from a past ancestor.
What are vestigial structures?
The process by which new species arise due to a population becoming reproductively isolated from other populations.
What is reproductive isolation?
This type of selection favors intermediate variants and acts against extreme phenotypes.
What is stabilizing selection?
The genetic variation within a population that can be acted upon by natural selection.
What is genetic diversity?
The naturalist who independently conceived the theory of evolution by natural selection and prompted Darwin to publish his own theory.
Who is Alfred Wallace?
The field that involves comparing the DNA and protein sequences of different organisms to infer evolutionary relationships.
What is Molecular Biology?
The term for when two species live in the same area but utilize different habitats and thus do not encounter each other.
What is ecological/habitat isolation?
Selection that occurs when conditions favor individuals at both extremes of a phenotypic range over intermediate phenotypes.
What is disruptive selection?
The contribution an individual makes to the gene pool of the next generation, relative to the contributions of other individuals.
What is fitness?
The concept that describes how all species of organisms arise and develop through the natural selection of small, inherited variations that increase the individual’s ability to compete, survive, and reproduce.
What is descent with modification?
The phenomenon where closely related species evolve similar traits independently due to similar environmental pressures.
What is convergent evolution?
This phenomenon occurs when a few individuals from a larger population establish a new population with a gene pool that is not reflective of the original population, often leading to rapid evolutionary changes and speciation.
What is the founder effect?
The type of natural selection that favors traits that increase an individual’s chance of mating and producing offspring.
What is sexual selection?
Structures in different species with a common ancestor or developmental origin but which serve different functions.
What are homologous structures?
Explains how individuals with traits better suited to their environment tend to survive and reproduce more successfully, passing on these advantageous traits to their offspring, while those less adapted tend to diminish over generations.
What is Natural Selection?
This type of selection occurs when humans breed plants and animals for particular genetic traits.
What is the artificial selection?
An effect caused by large population death due to natural events.
What is the bottleneck effect?
The principle stating that allele frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences.
What is the Hardy-Weinberg Equalibrium?