Evolutionary taxonomy

The idea of translating Linnaean taxonomy into a sort of dendrogram of the Animal and Plant kingdoms was formulated toward the end of the 18th century, well before Charles Darwin's book On the Origin of Species was published.

[7] The idea was popularised in the English-speaking world by the speculative but widely read Vestiges of the Natural History of Creation, published anonymously by Robert Chambers in 1844.

[9] Following Darwin's publication, Thomas Henry Huxley used the fossils of Archaeopteryx and Hesperornis to argue that the birds are descendants of the dinosaurs.

The resulting description, that of dinosaurs "giving rise to" or being "the ancestors of" birds, exhibits the essential hallmark of evolutionary taxonomic thinking.

The past three decades have seen a dramatic increase in the use of DNA sequences for reconstructing phylogeny and a parallel shift in emphasis from evolutionary taxonomy towards Hennig's 'phylogenetic systematics'.

[7] Today, with the advent of modern genomics, scientists in every branch of biology make use of molecular phylogeny to guide their research.

[citation needed] Thomas Cavalier-Smith,[7] G. G. Simpson and Ernst Mayr[11] are some representative evolutionary taxonomists.

Efforts in combining modern methods of cladistics, phylogenetics, and DNA analysis with classical views of taxonomy have recently appeared.

Cladistic analysis groups taxa by shared traits but incorporates a dichotomous branching model borrowed from phenetics.

This is not a model of evolution, but is a variant of hierarchical cluster analysis (trait changes and non-ultrametric branches.

Phylogenetics attempts to inject a serial element by postulating ad hoc, undemonstrable shared ancestors at each node of a cladistic tree.

[citation needed] The two approaches, evolutionary taxonomy and the phylogenetic systematics derived from Willi Hennig, differ in the use of the word "monophyletic".

Such paraphyletic groups are rejected in phylogenetic nomenclature, but are considered a signal of serial descent by evolutionary taxonomists.