Phylogenetics

A transitional fossil is any fossilized remains of a life form that exhibits traits common to both an ancestral group and its derived descendant group.

Wikispecies is a wiki-based online project supported by the Wikimedia Foundation.

Cladistics (from Greek κλάδος, klados, i.e., "branch") is an approach to biological classification in which organisms are categorized based on shared derived characteristics that can be traced to a group's most recent common ancestor and are not present in more distant ancestors.

In common cladistic usage, a monophyletic group is a taxon (group of organisms) which forms a clade, meaning that it consists of an ancestral species and all its descendants.

A polyphyletic (Greek for "of many races") group is characterized by one or more homoplasies: phenotypes which have converged or reverted so as to appear to be the same but which have not been inherited from common ancestors.

The Articulata hypothesis is the grouping in a higher taxon of animals with segmented bodies, consisting of Annelida and Panarthropoda.

The genetic history of Europe is complicated because European populations have a complicated demographic history, including many successive periods of population growth.

The Encyclopedia of Life (EOL) is a free, online collaborative encyclopedia intended to document all of the 1.

Molecular Phylogenetics and Evolution is a peer-reviewed scientific journal of evolutionary biology and phylogenetics.

The International Society for Phylogenetic Nomenclature was established to encourage and facilitate the development and use of, and communication about, phylogenetic nomenclature.

Cladistics is a bimonthly peer-reviewed scientific journal publishing research in cladistics.

Jacques Armand Gauthier is a vertebrate paleontologist, comparative morphologist, and systematist, and one of the founders of the use of cladistics in biology.

The Eocyte hypothesis is a biological classification that indicates eukaryotes emerged within the prokaryotic Crenarchaeota (formerly known as eocytes), a phylum within the archaea.

TreeFam defines a gene family as a group of genes that evolved after the speciation of single-metazoan animals.

OrthoDB presents a catalog of orthologous protein-coding genes across vertebrates, arthropods, fungi, plants, and bacteria.

The orthology predictions of OMA are available in several forms: * OMA Pairs: for a given gene, a list of predicted orthologs in other species is provided.

Mesquite is a software package primarily designed for phylogenetic analyses.

PhylomeDB includes also a public download section with the complete set of trees, alignments and orthology predictions, as well as a web API that facilitates cross linking trees from external sources.

The Catalogue of Life, started in June 2001 by Species 2000 and Integrated Taxonomic Information System (ITIS), is planned to become a comprehensive catalogue of all known species of organisms on Earth.