BioConcepts

type method

• The naming procedure for a biological species (or other taxonomic group such as a genus) by attaching a name to one (dead) individual (specimen) (in a public collection) and claiming that all other individuals which are conspecific to the chosen one (or which belong in the same higher taxonomic group) bear that name; thus the naming of a taxonomic group by linking an individual to a rigid designator.    

  1902

  The first and fundamental step to be taken is to fix generic names at one point by means of an assigned type, in case none was originally designated by the author. This method has already been proposed by Cook, and also by Underwood […] The type method in regard to species has gained general recognition so far as present practice is concerned, though we regret to say that one still occasionally sees new species described without the citation of a type specimen. The type method is equally or even more necessary and applicable in the case of genera    

  Shear, C.L. (1902). Generic nomenclature. Botanical Gazette 33, 220-229: 225-6.

  1914

  stability in botanical nomenclature is greatly aided by the adoption of the type method; that is, that for nomenclatorial purposes a genus shall be based upon a type species and a species upon a type specimen.    

  Hitchcock, A.S. (1914). The type species of Danthonia. Botanical Gazette 57, 328-330: 328.

  1924

  Under the type-method a specific name stands or falls by its type-specimen […]. Where several specimens were originally cited and none was designated as the type, a type-specimen should be selected in accordance with the following considerations. It should be the specimen on which the original description was based, or which the author had chiefly in mind. This may be indicated by closer agreement with the original diagnosis or description, by manuscript notes left by the author, or sometimes by the specific name.

  Davy, J.B. (1924). New Noteworthy South African plants, VI. Bulletin of Miscellaneous Information (Royal Botanic Gardens, Kew) 1924, 223-235: 226.    

  1929

  The essence of the type-method is the acceptance of a particular unit or so-called “type” to which each name is permanently attached (whether as an accepted name or as a synonym) however the limits of the group may be altered. The weakness of the type-method is that in many cases there is disagreement as to which unit should be regarded as the type, and in others there is no particular reason for regarding any unit as the type.

  Sprague, T.A. (1929). Principles and problems of plant nomenclature. Proceedings of the International Conress of Plant Sciences 2, 1422-1426: 1423. 

  2015

  Biological taxonomists rely on the so-called ‘type method’ to regulate taxonomic nomenclature. For each newfound taxon, they lay down a ‘type specimen’ that carries with it the name of the taxon it belongs to. Even if a taxon’s circumscription is unknown and/or subject to change, it remains a necessary truth that the taxon’s type specimen falls within its boundaries. Philosophers have noted some time ago that this naming practice is in line with the causal theory of reference and its central notion of rigid designation: a type specimen fixes the reference of a taxon name without defining it.   

  Witteveen, J. (2015). Naming and contingency: the type method of biological taxonomy. Biology and Philosophy 30, 569–586: 569.