the evolutionary history of a species or taxonomic group; the relationships by ancestry among species or taxonomic groups.
Derived character
a feature that evolved only within a particular taxonomic group.
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.
the science of describing, naming, and classifying organisms.
a phylogenic classification system that uses shared derived characteristics and ancestry as the sole criterion for grouping taxa.
Binomial nomenclature
a system for giving each organism a two-word scientific name that consists of the genus name followed by the species name.
Species identifier
the second part of an organisms name, the "species" part.
in a modern taxonomic system, the broadest category; the category that contains kingdoms.
in a traditional taxonomic system, a kingdom made of prokaryotes that can live in extreme environments; differentiated from other prokaryotes by various important chemical differences; biologists more recently prefer to classify these organisms as Domain Archaea.
in a traditional taxonomic system, a kingdom that contains all prokaryotes except Kingdom Archaebacteria (Domain Archaea); biologists more recently prefer to classify these organisms as Domain Bacteria.
in a traditional taxonomic system for plants, the category contained within a kingdom and containing classes.
in a traditional taxonomic system, a kingdom made up of eukaryotic, multicellular organisms that have cell walls made mostly of cellulose, that have pigments that absorb light, and that supply energy and oxygen to themselves and to other life-forms through photosynthesis.
an organism that is classified as a member of the kingdom Protista; generally, a single-celled or simple multicellular eukaryote that cannot be readily classified as either plant, animal, or fungus.
the variety of organisms considered at all levels from populations to ecosystems.
any particular group within a taxonomic system.
broadest category underneath Domain.
Subset below the kingdom.
subset below phyla.
subset below class.
subset below order.
subset below family.
variations of a species that live in different geographic areas.
the analysis of the evolutionary or ancestral relationships among taxa.
Phylogenetic diagram
looks like a family tree, and has a branching pattern that indicates how closely related a subset of taxa are thought to be.
Homologous features
items that share a common ancestry.
Analogous features
features that are similar because they have a similar function rather than a similar lineage.
Shared character
a feature that all members of a group have in common.
group of organisms that includes an ancestor plus all of its descendants.