Phylogenesis

Phylogenesis (from Greek φῦλον phylon "tribe" + γένεσις genesis "origin") is the biological process by which a taxon (of any rank) appears. The science that studies these processes is called phylogenetics.

These terms may be confused with the term phylogenetics, the application of molecular - analytical methods (i.e. molecular biology and genomics), in the explanation of phylogeny and its research.

Phylogenetic relationships are discovered through phylogenetic inference methods that evaluate observed heritable traits, such as DNA sequences or overall morpho-anatomical, ethological, and other characteristics.

The result of these analyses is a phylogeny (also known as a phylogenetic tree) – a diagrammatic hypothesis about the history of the evolutionary relationships of a group of organisms. Phylogenetic analyses have become central to understanding biodiversity, evolution, ecological genetics and genomes.

Cladistics (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. Therefore, members of a group are assumed to share a common history and are considered to be closely related.

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