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DNA barcoding for effective biodiversity assessment of a hyperdiverse arthropod group: the ants of Madagascar.

ABSTRACT: The role of DNA barcoding as a tool to accelerate the inventory and analysis of diversity for hyperdiverse arthropods is tested using ants in Madagascar. We demonstrate how DNA barcoding helps address the failure of current inventory methods to rapidly respond to pressing biodiversity needs, specifically in the assessment of richness and turnover across landscapes with hyperdiverse taxa. In a comparison of inventories at four localities in northern Madagascar, patterns of richness were not significantly different when richness was determined using morphological taxonomy (morphospecies) or sequence divergence thresholds (Molecular Operational Taxonomic Unit(s); MOTU). However, sequence-based methods tended to yield greater richness and significantly lower indices of similarity than morphological taxonomy. MOTU determined using our molecular technique were a remarkably local phenomenon-indicative of highly restricted dispersal and/or long-term isolation. In cases where molecular and morphological methods differed in their assignment of individuals to categories, the morphological estimate was always more conservative than the molecular estimate. In those cases where morphospecies descriptions collapsed distinct molecular groups, sequence divergences of 16% (on average) were contained within the same morphospecies. Such high divergences highlight taxa for further detailed genetic, morphological, life history, and behavioral studies.

SUBMITTER: Smith MA

PROVIDER: S-EPMC1609228 | biostudies-literature | 2005 Oct

REPOSITORIES: biostudies-literature

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DNA barcoding for effective biodiversity assessment of a hyperdiverse arthropod group: the ants of Madagascar.

Smith M Alex MA Fisher Brian L BL Hebert Paul D N PD

Philosophical transactions of the Royal Society of London. Series B, Biological sciences 20051001 1462

The role of DNA barcoding as a tool to accelerate the inventory and analysis of diversity for hyperdiverse arthropods is tested using ants in Madagascar. We demonstrate how DNA barcoding helps address the failure of current inventory methods to rapidly respond to pressing biodiversity needs, specifically in the assessment of richness and turnover across landscapes with hyperdiverse taxa. In a comparison of inventories at four localities in northern Madagascar, patterns of richness were not signi ...[more]

PMID: 16214741

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Dataset Information

DNA barcoding for effective biodiversity assessment of a hyperdiverse arthropod group: the ants of Madagascar.

Publications

DNA barcoding for effective biodiversity assessment of a hyperdiverse arthropod group: the ants of Madagascar.

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