A scientific discipline focused on classifying organisms and determining their evolutionary relationships
The two part scientific name of a species, consisting of genus and specific epithet. Instituted by Carolus Linnaeus in the 18th century
A branching diagram that represents the evolutionary history of a group of organisms
System of classification of organisms based on evolutionary relationships: Only groups that include a common ancestor and all of its descendants are named.
The two way points that represent the divergence of two evolutionary lineages from a common ancestor
Describes a phylogenetic tree that contains a branch point representing the last common ancestor of all taxa in the tree
The similarity between two species that is due to convergent evolution rather than to descent from a common ancestor
The discipline that uses DNA and other molecular data to determine evolutionary relationships
An approach to systematics in which organisms are placed into groups called clades based primarily on common descent
shared ancestral character
A character, shared by members of a particular clade, that originated in an ancestor of the taxon
shared derived characteristic
Evolutionary novelty unique to a particular clade that is not found in their ancestors
A species or group of species from an evolutionary lineage that is known to have diverged before the lineage that contains the group of species being studied.
In a cladistic study of evolutionary relationships among taxa of organisms, the group of taxa that is actually being analyzed
A principle that states that when considering multiple explanations for an observation, one should first investigate the simplest explanation that is consistent with the facts
A principle that states that when considering multiple phylogenetic hypotheses, one should take into account the one that reflects the most likely sequence of evolutionary events, given certain rules about how DNA changes over time
An approach in which features shared by two groups of organisms are predicted (by parsimony) to be present in their common ancestor and all of its descendants
A yardstick for measuring the absolute time of evolutionary change based on the observation that some genes and other regions of genomes appear to evolve at constant rates
The hypothesis that much evolutionary change in genes and proteins has no effect on fitness and therefore is not influenced by Darwinian natural selection
horizontal gene transfer
A process in which genes are transferred from one genome to another through mechanisms such as exchange of transposable elements and plasmids, viral infection, and perhaps fusions of organisms
Pertaining to a group of taxa that consists of a common ancestor and all its descendants.
Pertaining to a group of taxa that consists of a common ancestor and some, but not all, of its descendants