Scientific Nomenclature and its Discontents: Comments by Frost on Rules and Philosophy of Taxonomy, Ranks, and Their Applications

The International Code of Zoological Nomenclature (1999) is the governing rule-book for nomenclature in this catalogue. Although it can be unnecessarily arcane it has served to knit together the community of taxonomists for a very long time. Insofar as I can, this catalogue complies with the rules laid down by that Code for family-group, genus-group, and species-group taxa. The Code does not apply to unranked taxa named explicitly outside of that Code, or to ranked and unranked taxa above the family-group.

I have not adopted the unofficial rules devised by Alain Dubois (e.g., Dubois, 2005, 2006; Dubois et al., 2021) to augment the International Code by applying to ranks above the family-group. These extraordinary rules have not been adopted by the International Commission of Zoological Nomenclature, presumably for good reason and seem to be getting little traction outside of Dubois' immediate coterie of coauthors. That should be enough to preclude its adoption, but, in addition, I do not want to promote a system that lacks the imprimatur of the governing body, particularly when I suspect that most do not consider the current lack of regulation of categories above the family-group by the International Code to be much of a problem, much less an impediment to communication. As an example of how the supernumerary rules of Dubois can make for some counter-factual conclusions, Dubois and Raffaëlli (2012) assert that the authorship of the order Anura should be assigned to Duméril (1805) although Duméril explicitly refers to the "famille" Anoures, explicitly placing that non-Latin collective name squarely in what the Code now refers to as the family-group. Nevertheless, should the Commission adopt Dubois' recommended rules, I will follow them, but not happily, as I think that Dubois' approach to nomenclatural practice and his preoccupation with ranks is in part what, unfortunately, makes many biologists think of scientific nomenclature as the bastion of a self-appointed priesthood, and the whole practice a rococo vestige of times past. (See the recent editorial in Nature [Anon., 2013] for a well-written and pointed critique of Dubois' approach to nomenclature. I hardly agree with everything in the critique but do agree with enough of it that I think it is worth a read.) (See also Harold, 2013, BMC Blog Network for another response by BioMedCentral to Dubois' extreme views.) Because Bionomina appears to be Dubois' personal journal, criticism continues from Dubois in largely uncited articles about the rules of nomenclature he thinks are important. Unfortunately, these articles, evaluated through time have more in common with the the progression of Louis Wain's cat paintings than any real progress for systematics. And, indeed, the latest version of this approach to taxonomy and nomenclature (Dubois et al., 2021) is clearly for those interested in a vocabulary of distinctions without differences, although associated with a worthwhile tree done, clearly, entirely by Alex Pyron. As for Dubois' 10 taxonomic-ranking criteria, this is merely another example of the kind of arbitrary optimality criteria that rendered phenetic classifications extinct. It matters not how many criteria go into justifying a particular rank; it only matters what ranked names imply about the underlying tree. This issue of the questions requiring at least as much clarity as the answers was illustrated particularly well by "The Hitchikers  Guide to the Galaxy" where "the answer to life, the universe, and everything" was calculated to be 42. 

Logically unrelated but telling about mindset, Dubois and Raffaëlli (2012) have also criticized me and others rather extensively for formulating putatively non-euphonious scientific names. (I laughingly plead guilty to this non-crime, at least in some cases, although I, for one, find Bolitoglossa huehuetenanguensis [not named by me], one of their examples, to be quite euphonious, maybe because I have actually spent time in Huehuetenango, Guatemala.) And, beyond the fact that notions of euphony are largely a function of language, familiarity, and culture, it is hard to accept that Dubois should be the judge of what is euphonious, as he has formulated numerous new, unneeded, and non-euphonious terms (e.g., "didynonym", "distagmonym", and "sozodiaphonym") in order to resolve supposed nomenclatural problems that no one outside of his immediate circle considers problematic.  

Also, I have not adopted the PhyloCode (, regardless of its attractive features, because it has not been adopted by any scientific organization other than its immediate umbrella group (International Society for Phylogenetic Nomenclature) and because this approach does not seem to be gaining traction among systematists due to the nature of the inherent conflict in naming conventions with the International Code, and due to the fact that it is inherently more unstable than Linnaean nomenclature. Having said that, I think it is clear that judicious naming of unranked taxa, at least above the level of ICZN-regulated family-group names, has definitely brought considerable good, bringing into focus the fact that ranks do not (in fact, cannot) provide sets of comparable entities, and of more practical moment, acting as something of a pressure-valve that allows reconciliation of major groups under unranked names while allowing each to maintain its own family-group nomenclature. (For additional discussion see my comments in Higher Taxonomy and Progress.) As a result, we no longer have arguments beyond a few fringe authors about whether a taxon name should be ranked as a class, order, superorder, or subclass—hardly a worthwhile endeavor. 

Users should be aware that many authors apparently think they are meeting the criteria of the Code for purposes of electronic publication when, most frequently, they are not. Under the current Code (1999 + recent addenda), electronic publication requires, in addition to a list of standard and common-sense requirements: 1) the date of publication be stated in the work itself; 2) the publication be registered in the Official Register of Zoological Nomenclature (ZooBank) and 3) there be evidence presented in the work itself that such registration has taken place. I can name only a handful of publications that have met these requirements, but a relatively large number where the authors think they have met the requirements and have not. (Fortunately, Zootaxa is doing a good job on this front.) The dates in these cases extend from the dispersal of the paper publications, not from the appearance of the electronic version (see most taxonomic papers published in Systematic Biology, Zoologica Scripta, and Evolution, where pre-publication electronic preprints available online are the rule). Unfortunately, many journals with Early View (pre-publication) release of papers in electronic form (e.g., Cladistics, pretty much anything published by Wiley, African Journal of Herpetology, Molecular Ecology, Genetica, Conservation Genetics, Ecology and Evolution, Systematics and Biodiversity) are not doing their authors any favors by putting their work at risk for piracy this way. 

And, of course, there is the issue of the wobble among taxonomic ranks within categories. Where there is a controversy such as between family or subfamily, genus or subgenus, my inclination is to adopt the more particulate solution (although I have my limits). In part this is due to not wanting to spend time going back and forth as some of these things are destined to go. But, increasingly, I am struck that finer-grained taxonomies promote additional work and informal and cryptic collectives do not. In particular, the use of subgenus (an obscure rank at best) seems to have more to do with political gamesmanship (so what is the Linnean equivalent of the non-Linnean Novirana?), a way of concealing testable hypotheses under the rubric of stability, than anything that promote systematists to test each others' hypotheses. 


Anonymous. 2013. Editorial: The new zoo. Nature, 503: 311–312.

Dubois, A. 2005. Proposed Rules for the incorporation of nomina of higher-ranked zoological taxa in the International Code of Zoological Nomenclature. 1. Some general questions, concepts and terms of biological nomenclature. Zoosystema. Paris 27: 365–426.

Dubois, A. 2006. Incorporation of nomina of higher-ranked taxa into the International Code of Zoological Nomenclature: some basic questions. Zootaxa 1337: 1–37.

Dubois, A., A. Ohler, and A. Pyron. 2021. New concepts and methods for phylogenetic taxonomy and nomenclature in zoology, exemplified by a new ranked cladonomy of recent amphibians (Lissamphibia). Megataxa 5: 1–738. 

Dubois, A., and J. Raffaëlli. 2012. A new ergotaxonomy of the order Urodela Duméril, 1805 (Amphibia, Batrachia). Alytes. Paris 28: 77–161.

Duméril, A. M. C. 1805. Zoologie Analytique, ou Méthode Naturelle de Classification des Animaux, Rendue plus Facile à l’Aide de Tableaux Synoptiques. Paris: Allais.

Harold, S., E. Moylan, T. Sands, P. Harris, M. Kowalczuk, M. Torkar, and R. Francis. . 2013. The devil may be in the detail, but the longview is also worth a look. BMC Blog Network.

ICZN. 1999. International Code of Zoological Nomenclature. Fourth edition. London, U.K. [available online at ]: International Trust for Zoological Nomenclature.