Classification

clade

A clade is a group of organisms that includes an ancestor and all of its descendants. Clades are based on cladistics. This is a method of comparing traits in related species to determine ancestor-descendant relationships.

domain

A domain is a taxon that is larger and more inclusive than the kingdom. Most biologists agree there are three domains of life on Earth: Bacteria, Archaea, and Eukaryota

Linnaean classification system

All modern classification systems have their roots in the Linnaean classification system

genus

Closely related species are grouped together in a genus.

phylogeny

Phylogeny is the evolutionary history of a group of related organisms.

Phylogenetic tree

Phylogeny is the evolutionary history of a group of related organisms. It is represented by a phylogenetic tree

taxa

The Linnaean system of classification consists of a hierarchy of groupings, called taxa (singular, taxon). Taxa range from the kingdom to the species

kingdom

The kingdom is the largest and most inclusive grouping. It consists of organisms that share just a few basic similarities. Examples are the plant and animal kingdoms

taxonomy

The science of classifying organisms is called taxonomy.

species

The species is the smallest and most exclusive grouping. It consists of organisms that are similar enough to produce fertile offspring together.

binomial nomenclature

This method, called binomial nomenclature, gives each species a unique, two-word Latin name consisting of the genus name and the species name. An example is Homo sapiens, the two-word Latin name for humans. It literally means "wise human." This is a reference to our big brains.