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Tree

Based on similarity and dissimilarity of genomes, one can organize various species / classes of organisms into a tree.

Species of cellular life

The top branches (superregna) are: archaea, bacteria and eukaryota (true nucleus). The prior two are called prokaryota (primitive - neucleus).

The top branches of Eukaryota (regna) include plants, animals, fungi and protista (amoeba and some other primitive classes of organisms).

A notable branch of animals include the phylum chordata - subphylum vertebrata. The subphylum vertebrata includes classes named mammals, fish, reptiles, birds, amphibians.