Saturday, October 08, 2005

The Royal Society - Article:

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

(M. Alex Smith, Brian L. Fisher, Paul D.N. Hebert)

The role of DNA barcoding as a tool to accelerate the inventory and analysis of diversity for hyperdiverse arthropods was tested using ants in Madagascar. Smith et al. 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.
Inventories at four localities in northern Madagascar were compared: 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 their molecular technique were a local phenomenon, indicating highly restricted dispersal and/or long-term isolation.
In cases where their 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 on average 16% were contained within the same morphospecies - which might highlight taxa for further detailed studies (on genetics, morphology, life history, and behavior).

Towards writing the encyclopaedia of life: an introduction to DNA barcoding (Vincent Savolainen, Robyn S. Cowan, Alfried P. Vogler, George K. Roderick, Richard Lane)