Biodiversity, conservation and the “taxonomic impediment”.

1. This paper highlights the poor esteem in which taxonomy, as autonomous science, is held and the relative implications of this for conservation biology. 2. In recent times, taxonomy at the species level has tended to be neglected not just within ecological researches, but also in the identification and justification for the selection of the marine protected areas (MPA). A traditional criterion for choosing an MPA is the conservation of biodiversity, but most of the Italian MPA were chosen without initial detailed studies on their biodiversity, so that lists of species of the main invertebrate groups are not available. 3. The identification of organisms within communities to species level is one of the greatest constraints in terms of time and costs in ecological studies. Some studies have suggested that working at a taxonomic level higher than species does not result in an important loss of information (Taxonomic sufficiency). It does, however, lead to an inaccuracy of biodiversity evaluation which is, especially important when comparing different areas, and can lead to an ‘a priori’ exclusion of some entities before understanding their role in ecology. 4. Taxonomy has always been considered a marginal science even during the pioneer descriptive period of ecology, and traditionally has received little financial support. The result was the production of many misidentifications and erroneous records. During recent years, the developing experimental ecological approach has led to an improvement in scientific methods, but concurrently to a reduction in the number of expert taxonomists for many invertebrate groups. Descriptive works, historically so common in the Mediterranean area, are now considered obsolete, despite having an intrinsic value. 5. Biodiversity, particularly ‘species richness’ has long been thought to influence temporal variability and it seems that efforts to clarify the biodiversity/temporal variability relationship or to demonstrate the lack of such a relationship should continue. Such information is essential in order to maintain the ecological function despite the loss of component species, an important topic not only to ecologists but also to policy makers. Many species appear to have overlapping niches, and as such it could be argued that it is not essential for all species to be present. In contrast the crucial role of keystone species has been embraced in conservation biology as a tool to help highlight species requiring priority for protection.