click below
click below
Normal Size Small Size show me how
Gullett-Bio-Unit4
Biology-Unit4-Evolution
Term | Definition |
---|---|
evolution | the process of change by which new species develop from preexisting species over time |
species | a group of organisms that are closely related and can mate to produce fertile offspring; also the level of classification below genus and above subspecies |
fossil | the trace or remains of an organism that lived long ago, most commonly preserved in sedimentary rock |
variation | differences in physical traits of an individual from the group to which it belongs |
adaptation | the process of becoming adapted to an environment; an anatomical, physiological, or population's ability to survive |
biogeography | the study of the geographical distribution of living organsims and fossils on Earth |
homologous structure | body part that is similar in structure on different organisms but performs different functions |
analogous structure | body part that is similar in function as a body part of another organism but is structurally different |
vestigial structure | remnants of an organ or structure that functioned in an earlier ancestor |
gene flow | the movement of genes into or out of a popoulation due to interbreeding |
genetic dift | the random change in allele frequency in a population |
bottleneck effect | genetic drift that results from an event that drastically reduces the size of population |
founder effect | genetic drift that occurs after a small number of individuals colonize a new area |
sexual selection | an evolutionary mechanism by which traits that increase the ability of individuals to attact or acquire mates appear with increaseing frequency in a population |
reproductive isolation | a state in which a particular set of populations can no longer interbreed to produce future generations of offspring |
speciation | the formation of new species as a result of evolution |
behavioral isolation | isolation between population due to differences in courtship or mating behavior |
geographic isolation | isolation between populations due to physical barriers |
temporal isolation | isolation between populations due to barriers related to time, such as differences in mating periods or differences in the time of day that individuals are the most active |
convergent evolution | the process by which unrelated species became more similar as they adapt to the same kind of environment |
divergent evolution | evolution of one or more closely related species into differen species; resulting from adaptations to different environmental conditions |
coevolution | the evolution of two or more species that is due to mutual influence often in a way that makes the relationship more mutually beneficial |
extinction | the death of every member of a species |
cyanobacteria | bacteria that can carry out photosynthesis |
endosymbiosis | a mutually beneficial relationship in which one orgnaism lives within another |
phylogeny | the evolutionary history of a species or taxonomic group |
cladistics | a phylogenetic classification system that uses shared derived characters and ancestry as the sole criterion for grouping taxa |
cladogram | a diagram that is based on patterns of shared derived traits and that shows the evolutionary relationships between groups of organisms |
derived character | a feature or trait involved only within a particular taxonomic group |
taxonomy | the science of describing, naming and classifying organsisms |
taxon | any taxonomic group of any rank in a hierarchical classification of organisms,; for example: genus, species, or class |
binomial nomenclautre | a system for giving each organisms a two -word scientific name that consists of the genus name followed by the species name. |
genus | the level of classification that comes after family and contains similar species |
domain | the most broad taxon for classifying living organisms of which there are three: Bacteria, Archaea, and Eukaryota |