The Coelurosauria are a group of mostly feathered theropods that gave rise to birds, the only dinosaurs that survived the Cretaceous-Paleogene extinction event and are still found today. Between their first appearance in the Middle Jurassic up to the end Cretaceous, coelurosaurs were party to dramatic geographic changes on the Earth's surface, including the breakup of the supercontinent Pangaea, and the formation of the Atlantic Ocean. These plate tectonic events are

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Molecular sequence information about viruses has mostly confirmed the groupings devised by traditional taxonomic methods, but shown in addition that the genes of related species may differ in number, arrangement, orientation and in sequence homology. It has also revealed that true genetic recombination between viruses has been common, even among those with RNA genomes, indeed most virus groups seem to have arisen y recombination. Thus, there is an unexpected wealth of genetic chaos hidden behind the fatade of the phenotype, and it is possible that the difficulties that plant taxonomists have had in identifying the relationships of the major groupings of plants could have similar causes. Nonetheless, molecular taxonomy does give sensible results and this is illustrated by a classification of the large subunit Rubisco proteins of 21 plant species based on their amino acid sequences.