Interpreting the universal phylogenetic tree.

C R Woese

doi:10.1073/pnas.97.15.8392

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Interpreting the universal phylogenetic tree.

C R Woese

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Abstract

The universal phylogenetic tree not only spans all extant life, but its root and earliest branchings represent stages in the evolutionary process before modern cell types had come into being. The evolution of the cell is an interplay between vertically derived and horizontally acquired variation. Primitive cellular entities were necessarily simpler and more modular in design than are modern cells. Consequently, horizontal gene transfer early on was pervasive, dominating the evolutionary dynamic. The root of the universal phylogenetic tree represents the first stage in cellular evolution when the evolving cell became sufficiently integrated and stable to the erosive effects of horizontal gene transfer that true organismal lineages could exist.

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Cell Size Evolution, Molecular Gene Transfer, Horizontal Genetic Variation Phylogeny RNA, Ribosomal NASA Discipline Exobiology Non-NASA Center Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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C R Woese. 2000-07-18. Interpreting the universal phylogenetic tree.. https://doi.org/10.1073/pnas.97.15.8392

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