| RBGE Lichens (Home) > Taxonomy and Systematics | ||||||||
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| Taxonomy and Systematics |
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> Taxonomy is the science which documents the Earth's biodiversity, our shared biological heritage generated over 3.8 billion years of evolution. Systematics seeks to understand the evolutionary relationships among the described species. > RBGE has a strong research tradition in lichen taxonomy and systematics. The RBGE Herbarium > The fundamental resource for taxonomy is the herbarium (Figure 1), which includes a large collection of example lichen specimens. Similar to a world-class museum, which protects and interprets cultural artefacts on behalf of the nation, the herbarium collects and archives specimens for the description and interpretation of the Earth's biodiversity. > The herbarium at RBGE houses an historically important collection of lichens. Among the oldest specimens are those collected during the global voyages of Archibald Menzies during late 18th Century. Additionally, there are important international collections by J. Hooker (e.g. sub-Antarctic Islands: Figure 2), by Lauder Lindsay (New Zealand and Iceland) and by Eaton during the 'Transit of Venus' Expedition to the Southern Ocean (e.g. Kerguelan, 1874). Among the extensive British and Scottish material are collections by Borrer (included as part of Brodie's material), Greville, McAndrew and Ursula Duncan. Species Description > With the appointment of Brian Coppins in the early 1970s (Figure 3), RBGE came to play a leading role in the taxonomy of British lichens. Consequently, the lichen herbarium has an unparalleled reputation for its modern and comprehensive collection of British material. Collections by Brian (> 25,000 specimens) have focussed especially on difficult lichen groups (e.g. Micarea, and sterile crusts generally), and under Brian's leadership the herbarium at RBGE came to represent a facility which under-pins our current knowledge of the British lichen flora. > Classical taxonomic approaches continue at RBGE; additionally, there has been an increasing use of molecular tools, especially DNA barcoding, to further resolve lichen diversity. > DNA barcoding is based on the selection of a small number of gene regions, which can provide near-universal tools to discriminate between many species. The barcoding process is iterative, and new information provided by molecular biology is part of a cycle of discovery, in which traditional morphological species concepts can be refined. RBGE's initial work on lichen barcoding had two components: 1. The application of barcoding at a floristic scale, to test the universality of the approach across a wide range of lichenised-Ascomycetes, 2. The targeted study of a difficult genus - Usnea - to test barcoding as a tool to resolve species concepts and aid identification within notoriously difficult genera. Species Inventory > Taxonomists play an important role in documenting species distributions, generating species checklists at local, regional and national levels. These data are fundamentally important in writing Floras, Checklists, and as a resource in biogeography and conservation biology. > RBGE taxonomy has been pivotal in publication of the The Lichen Flora of Great Britain and Ireland, The Checklist of British and Irish Lichens (and accompanying Synonym List), and A Conservation Evaluation of British and Irish Lichens. Together these publications represent an unprecedented resource supporting British conservation. Much of RBGE's field recorded data is now digitised and freely available via the NBN Gateway. Taxonomic Resources |
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