A new paper in the Proceedings of the National Academy of Science explores the way in which new species of plants are described from specimens that may already have been in herbarium collections for many years, and underlines the importance of collections for discovering diversity..

NHM scientist Dr Mark Carine and scientific associate Dr Norman Robson undertook the research with colleagues from the Earthwatch Institute; University of Oxford; Royal Botanic Garden Edinburgh; Royal Botanic Gardens Kew; and the Missouri Botanical Garden, looking at the time between the acquistion of the specimens and publication of the plant's description in the Kew Bulletin.

A small number of specimens are recognised as being new species when they are first collected.  However, the scientists found that many others are identified as a result of comparisons and revisions of major groups of plants that take place more gradually within the large collections, sometimes taking several years.  In this process, many specimens from different herbaria will be compared: the comparison and analysis gives rise to new understanding of diversity and the identification and description of new species.

This work emphasises the importance of collections, such as those of the NHM and its partners, in improving understanding of plant diversity. These collections exchange many specimens each year, and make thousands of loans to enable scientists to work on plant diversity around the world.  They are increasingly developing digital resources that should give wider and more rapid access to images of plant specimens, supporting this area of science.

Bebber, DP, Carine, MA, Wood, JRI, Wortley, AH, Harris, DJ, Prance, GT, Davids, G, Paige, J, Pennington, TD, Robson, NKB and Scotland, RW (2010) Herbaria are a major frontier for species discovery.  PNAS.  Published online before print, December 6, 2010, doi: 10.1073/pnas.1011841108