Zoological Nomenclature Between Dream and Drama - Names For Concepts Or Concepts Despite Names? <B>Zoological Nomenclature Between Dream and Drama - Names For Concepts Or Concepts Despite Names?</B><P> <EM><B></B></EM><B>Alessandro Minelli</B><P> President, International Commission on Zoological Nomenclature<BR> Dipartimento di Biologia, Universit++ di Padova, Via Trieste 75, I 35121, Padova, Italy<P> 1.The uncritical use of the Linnaean hierarchy and of the binomial nomenclature has made, in the long run, a disservice to biological systematics. Uniformity of nomenclatural treatment has all too often concealed fundamental problems both in grouping lower taxa together and in assigning ranks to taxa. These problems were already emerging in the scientific literature of the late XVIII century (e.g., Adanson) but still too often remain outside the understanding and, especially, the practice of researchers. In a kind of perverted logic, we witness sometimes, rather than an effort to establish a convenient nomenclature to convey theoretically sound concepts, a deliberate effort to establish concepts to justify continuing use of a traditional nomenclature.<BR> 2. In spite of the principles advocated by the current Codes, the mutual independence of taxonomy and nomenclature is a certainly desirable goal, but it is probably unattainable.<BR> 3. Within the provisions of the International Code of Zoological Nomenclature, there is no place for animals not obviously belonging to species, e.g., for hybrids. On the other hand, no Code allows for a differential nomenclatural treatment of 'biological species' and the taxonomic units of uniparental organisms ('agamospecies' or 'microspecies'). According to several authorities, however, these organisms do not form species. If we agree with this view, how can we accept that they are namedas if they are species? We cannot exceedingly blame the users of nomenclature for adding apples and cherries so far as we, the producers of taxonomy and taxonomic nomenclature, ruthlessly conceal this amazing and still problematic diversity of objects and concepts under the quiet veil of one and the same kind of names (Linnean binomina).<BR> 4. Formulae where a generic name is followed by an accession number or a locality name are not at all rare in papers dealing with molecular systematics or cytogenetics of some critical species groups. In many cases, the use of formulae rather than formal species names is not an expression of contempt towards traditional systematics and nomenclature, but the confessed perception that not everything in the living world does fit into our traditional taxonomic schemes. <BR> 5. We need to understand what, if anything, lies behind the terms kingdom and phylum. The natural sciences inherited from folk taxonomy a basic split between the plant and the animal kingdom. Accordingly, there was no reason to look for homologous parts between representatives of these two worlds. Cuvier narrowed further the possible scope of comparative morphology, when he established his four embranchements (Vertebrates, Articulates, Molluscs and Radiates), each of them corresponding to a basically unique body plan, hardly comparable to those of the other embranchements. The higher taxa called phyla in our current classifications are simply the heirs of this Cuvierian tradition: these higher (or highest) taxa are still implicitly perceived is so basically distinct from all other taxa of the same rank (whatever this expression may mean), as not to require any further effort to homologize their features with those of organisms classified in other phyla.<BR> 6.Absolute ranks are a dangerous myth. The existence of categorial ranks encourages spurious comparisons between entities assigned to the same rank but that are not otherwise comparable.<BR> Are there solutions to these problems?<BR> 1. We should improve our awareness of the conceptual and linguistic requirements of modern biological systematics, irrespective of their compatibility with traditional nomenclature.<BR> 2. Moreover, we must seriously try to understand the reasons behind the now widespread dissatisfaction with the Linnaean hierarchy.<BR> 3. Several people see, either with approval or with anxiety, that current trends in nomenclature could (or should) lead to the development of a 'double nomenclature', one side being for the phylogenetic system, the other side for the traditional, user-friendly classification.<BR> There are several arguments, allowing us to hope that the system and the classification may actually enjoy a mutually compatible, if not completely identical, nomenclatural treatment: (i) a system of nested monophyletic units is topologically arranged as a hierarchy, in the same way as a classification; (ii) many monophyletic units within the system are likely to be coextensive with conventional taxa identified as classes, within a classification; (iii) a well-worked system leads to the recognition of a variety of branching levels, but these do not necessarily all need a formal name or even acknowledgement in terms of rank. Therefore, I believe that system and classification should be developed side by side, in a strictly linked way and with the following provisos: (i) that we carefully develop a nomenclature suitable to convey the wealth of concepts burgeoning in modern systematics; (ii) that we care, as far as possible, for a mutual compatibility between the names used for the system and those for the classification.<P>