Darwins term for selective breeding: Breeding of organisms selected for certain traits in order to produce offspring with those traits.
A theory of evolution developed by Darwin, based on four ideas: excess reproduction, variations, inheritance, and the advantages of specific traits in an environment. Acts to select individuals that are best adapted for survival and reproduction.
Hereditary changes in groups of living organisms over time.
A structure that has the same function but different construction and was not inherited from a common ancestor.
More-primitive characteristic that appeared in common ancestors.
The study of the distribution of plants and animals on earth.
Morphological adaptations that allow organisms to blend into their environment.
A new feature that had not appeared in common ancestors.
Organism's early prebirth stage of development.
A measure of a trait's relative contribution to the following generation.
Anatomically similar structure inherited from a common ancestor.
Morphological adaptation in which one species evolves to resemble another species for protection or other advantages.
Reduced form of a functional structure that indicates shared ancestry.
Can occur in a relatively short time when one species gives rise to many different species in response to the creation of new habitats or some other ecological opportunity. Follows larg-scale extinction events.
A physical barrier divides on population into two or more populations.
Process in which a large population declines in number, then rebounds.
Random effect that can occur when a small population settles in an area separated from the rest of the population and interbreeds, producing unique allelic variations.
A change in the allelic frequencies in a population that is due to chance. In smaller populations, the effects of genetic drift become more pronounced, and the chance of losing an allele becomes greater. (bacteria vs antibiotics)
Rate of Speciation -Theory that evolution occurs in small, gradual steps over time.
(Mechanisms of Evolution) - Population genetics -This principle states that when allelic frequencies remain constant, a population is in genetic equilibrium.
Theory that evolution occurs with relatively sudden periods of speciation followed by long periods of stability.
Change in the frequency of a trait based on competition for a mate.
A species evolves into a new species without a physical barrier. The ancestor species and the new species live side by side during the speciation process.
Increases genetic variation within a population and reduces differences between populations
Promotes inbreeding and could lead to a change in allelic proportions favoring individuals that are homozygous for particular traits.
The relationship between two species might be so close that the evolution of one species affects the evolution of the other species. - Mutualism
Unrelated species evolve similar traits even though they live in different parts of the world
Rate of Speciation - explains rapid spurts of genetic change causing species to diverge quickly