Taxonomic Inflation and the Stability of Species Lists: The Perils of Ostrich's Behavior

Finding a new species is amongst the most important discoveries a biologist can make (Wilson, 1998). The discovery of new species opens up countless research possibilities, because species are the primary objects of study in many research fields of biology, and the species is the taxonomic unit most commonly used for conservation planning and management (Margules and Pressey, 2000). The formal description of species is one of several major research themes of taxonomy (e.g., Cracraft, 2002) and, hence, a fundamental part of the science of biodiversity (Wilson, 1988, 1992, 2003, 2004; Wheeler, 1995, 2004; Butler, et al., 1998; Disney, 1998; Causey et al., 2004). Thousands of new species are described each year and many still await description (e.g., May, 1988; Purvis and Hector, 2000; Meier and Dikow, 2004). However, despite the increasing rate of discovery, we are in the course of a major biodiversity crisis (Wilson, 1988). This has caused taxonomy to undergo a revival (Wheeler et al., 2004). Nevertheless, funds for taxonomy remain scarce and it is not strongly encouraged or promoted by academics (Dubois, 2003). But taxonomy has evolved, acquiring a better understanding of what species are and finding new tools to infer their boundaries (Mayr, 1942; Wiley, 1978; Cracraft, 1983; De Queiroz, 2005a).