1.
Binomial: The two-part latinized name of a species, consisting of the genus and specific epithet
2.
Branch Points: the representation on a phylogenetic tree of the divergence of two or more taxa from a common ancestor. Most branch points are shown as dichotomies, in which a branch representing the ancestral lineage splits into two branches, one for each of the two descendant taxa
3.
Clades: group of species that includes an ancestral species and all its descendants
4.
Cladistics: an approach to systematics in which organisms are placed into groups called clades based primarily on common descent
5.
Classes: taxonomic category above the level of order
6.
Domains: taxonomic category above the kingdom level. The three domains are Archaea, Bacteria, and Eukarya
7.
Family: in classification, the taxonomic category above genus
8.
Genus: A taxonomic catergory above the species level, designated by the first word of a species' two-part scientific name
9.
Homoplasies: Analogous structures that arose indepentdently
10.
Horizontal Gene Transfer: transfer of genes from one genome to another through mechanisms
11.
Ingroup: a species or group of species whose evolutionary relationships we seek to determine
12.
Kingdoms: the second broadest after domain
13.
Maximum Likelihood: a principle that states that when considering multiple phylogenetic hypotheses, one should take into account the hypothesis that reflects the most likely sequence of evolutionary events, given certain rules about how DNA changes over time
14.
Maximum Parsimony: 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
15.
Molecular Clock: method for estimating the time required for a given amount of evolutionary change, based on the observation that some regions of genomes appear to evolve at constant rates
16.
Molecular Systematics: the discipline that uses DNA and other molecular data to determine evolutionary relationships
17.
Monophyletic: pertaining to a group of taxa that consists of a common ancestor and all its descendants; a monophyletic taxon is equivalent to a clade
18.
Neutral Theory: the hypothesis that much evolutionary change in genes and proteins has no effect on fitness
19.
Orders: the taxonomic category above the level of family
20.
Orthologous Genes: Homologous genes that are found in different species because of speciation
21.
Outgroup: a species or group of species from an evolutionary lineage that is known to have diverged from the lineage that contains the group of species being studied. An outgroup is selected so that its members are closely related to the group of species being studied, but not closely related as any study-group members are to each other.
22.
Paralogous Genes: Homologous genes that are found on the same genome as a result of gene duplication
23.
Paraphyletic: pertaining to a group of taxa that consists of a common ancestor and some, but not all, of its descendants
24.
Phyla: taxonomic category above the level of class
25.
PhyloCode: System of classification of organisms based on evolutionary relationships; only groups that include a common ancestor and all of its descendants are named
26.
Phylogenetic Bracketing: An approach in which features shared by two groups of organisms are predicted to be present in their common ancestor and all of its descendants
27.
Phylogenetic Tree: A branching diagram that represents a hypothesis above the evolutionary history of a group of organisms
28.
Phylogeny: the evolutionary history of a species or group of species
29.
Polyphyletic: pertaining to a group of taxa derived from two or more different ancestors
30.
Polytomy: a branch point from which more than two descendant groups emerge
31.
Rooted: branch point within the tree represents that last common ancestor of all taxa in the tree
32.
Shared Ancestral Character: a character, shared by members of a particular clade, that originated in an ancestor that is not a member of that clade
33.
Shared Derived Character: an evolutionary novelty that is unique to a particular clade
34.
Sister Taxa: Groups of organisms that share an immediate common ancestor and hence are each other's closest relatives
35.
Systematics: a discipline focused on classifying organisms and determining their evolutionary relationships
36.
Taxon: named taxonomic unit at any given level of classification
37.
Taxonomy: scientific discipline concerned with naming and classifying the diverse forms of life
