Inferindo unidades evolucionariamente significantes de diversidade bacterial de pesquisas ambientais amplas de dados de um só locus

Inferring evolutionarily significant units of bacterial diversity from broad environmental surveys of single-locus data

Timothy G. Barraclough1,*, Martin Hughes1,2, Natalie Ashford-Hodges1 and Tomochika Fujisawa1,2

- Author Affiliations

1NERC Centre for Population Biology and Division of Biology, Imperial College London Silwood Park Campus, Ascot, Berkshire SL5 7PY, UK

2Department of Entomology, Natural History Museum London SW7 5BD, UK

Author for correspondence (t.barraclough@imperial.ac.uk)

Abstract

By far the greatest challenge for diversity studies is to characterize the diversity of prokaryotes, which probably encompasses billions of species, most of which are unculturable. Recent advances in theory and analysis have focused on multi-locus approaches and on combined analysis of molecular and ecological data. However, broad environmental surveys of bacterial diversity still rely on single-locus data, notably 16S ribosomal DNA, and little other detailed information. Evolutionary methods of delimiting species from single-locus data alone need to consider population genetic and macroevolutionary theories for the expected levels of interspecific and intraspecific variation. We discuss the use of a recent evolutionary method, based on the theory of coalescence within independently evolving populations, compared with a traditional approach that uses a fixed threshold divergence to delimit species.

Keywords:

bacteria 16S rRNA species DNA barcodes diversity

Footnotes

One contribution to a Special Feature on ‘Whole organism perspectives on understanding molecular evolution’.

Received February 4, 2009.

Accepted March 13, 2009.
© 2009 The Royal Society

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