Binomial Nomenclature - Value

Value

The value of the binomial nomenclature system derives primarily from its economy, its widespread use, and the uniqueness and stability of names it generally favors:

• Economy. Compared to the polynomial system which it replaced, a binomial name is shorter and easier to remember. It corresponds to the widespread system of family name plus given name(s) used to name people in many cultures.
• Widespread use. The binomial system of nomenclature is governed by international codes and is used by biologists worldwide.
• Clarity. Binomial names avoid the confusion that can be created when attempting to use common names to refer to a species. Common names often differ even from one part of a country to another, and certainly vary from one country to another. In English-speaking parts of Europe, the bird called a "robin" is Erithacus rubecula. In English-speaking North America, a "robin" is Turdus migratorius. In contrast, the scientific name can be used all over the world, in all languages, avoiding confusion and difficulties of translation.
• Uniqueness. Provided that taxonomists agree as to the limits of a species, it can have only one name that is correct under the appropriate nomenclature code, generally the earliest published if two or more names are accidentally assigned to a species. However, establishing that two names actually refer to the same species and then determining which has priority can be a difficult task, particularly if the species were named by biologists from different countries, so that in reality, a species may have more than one regularly used name (these are "synonyms").
• Stability. Although stability is far from absolute, the procedures associated with establishing binomial names tend to favor stability. For example, when species are transferred between genera (as not uncommonly happens as a result of new knowledge), if possible the second part of the binomial is kept the same. Thus there is disagreement among botanists as to whether the genera Chionodoxa and Scilla are sufficiently different to be kept separate. Those who keep them separate give the plant commonly grown in gardens in Europe the name Chionodoxa siehei; those who do not give it the name Scilla siehei. The siehei element is constant. Similarly if what were previously thought to be two distinct species are demoted to a lower rank, such as subspecies, where possible the second part of the binomial name is retained as the third part of the new name. Thus the Tenerife robin may be treated as a different species from the European robin, in which case its name is Erithacus superbus, or as only a subspecies, in which case its name is Erithacus rubecula superbus. The superbus element of the name is constant. Since taxonomists can legitimately disagree as to whether two genera or two species are distinct or not, more than one name can be in use.