DOI: 10.1126/science.284.5423.2124. Phylogenetic Classification and the Universal Tree

Phylogenetic Classification and the Universal Tree

10.1126/science.284.5423.2124

Crossref journal-article

American Association for the Advancement of Science (AAAS)

Science (221)

Abstract

From comparative analyses of the nucleotide sequences of genes encoding ribosomal RNAs and several proteins, molecular phylogeneticists have constructed a “universal tree of life,” taking it as the basis for a “natural” hierarchical classification of all living things. Although confidence in some of the tree's early branches has recently been shaken, new approaches could still resolve many methodological uncertainties. More challenging is evidence that most archaeal and bacterial genomes (and the inferred ancestral eukaryotic nuclear genome) contain genes from multiple sources. If “chimerism” or “lateral gene transfer” cannot be dismissed as trivial in extent or limited to special categories of genes, then no hierarchical universal classification can be taken as natural. Molecular phylogeneticists will have failed to find the “true tree,” not because their methods are inadequate or because they have chosen the wrong genes, but because the history of life cannot properly be represented as a tree. However, taxonomies based on molecular sequences will remain indispensable, and understanding of the evolutionary process will ultimately be enriched, not impoverished.

Bibliography

Doolittle, W. F. (1999). Phylogenetic Classification and the Universal Tree. Science, 284(5423), 2124â2128.

Authors 1

W. Ford Doolittle (first)

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I thank J. Logsdon A. Roger D. Faguy O. Feeley and Y. Inagaki for critical discussions and the Medical Research Council of Canada and the Canadian Institute for Advanced Research for support. I am indebted to J. P. Gogarten and W. Martin for persuading me of the importance of LGT.

Dates

Type	When
Created	23 years ago (July 27, 2002, 5:42 a.m.)
Deposited	1 year, 7 months ago (Jan. 13, 2024, 4:40 a.m.)
Indexed	4 days, 8 hours ago (Aug. 22, 2025, 12:45 a.m.)
Issued	26 years, 2 months ago (June 25, 1999)
Published	26 years, 2 months ago (June 25, 1999)
Published Print	26 years, 2 months ago (June 25, 1999)

Funders 0

None

JSON

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