Biological classification

In biological classification, a species is assigned a two-part name, treated as Latin. The genus is listed first (with its leading letter capitalized), followed by a second term. For example, gray wolves belong to the species Canis lupus, coyotes to Canis latrans, golden jackals to Canis aureus, etc.; and all of these belong to the genus Canis (which also contains many other species). The name of the species is the whole binomial, not just the second term (which may be called specific epithet for animals, or specific name for animals).

The binomial naming convention, later formalized in the biological codes of nomenclature, was first used by Leonhart Fuchs and introduced as the standard by Carolus Linnaeus in the 1700s and as a result is sometimes called the "binomial nomenclature". At this time, the chief biological theory was that species represented independent acts of creation by God, and were therefore considered objectively real and immutable.

Species

For a more detailed treatment, see species.

In biology, a species is one of the basic units of biological classification (see the diagram at the side - a genus contains one or more species, etc.) A usable definition of the word "species" and reliable methods of identifying particular species are essential for stating and testing biological theories and for measuring biodiversity. A species consists of individual organisms which are very similar in appearance, anatomy, physiology and genetics. Evolutionists assume this is due to having relatively recent common ancestors. Traditionally, multiple examples of a proposed species must be studied for unifying characters before it can be regarded as a species.

The commonly used names for types of animal in English and many other languages often do not correspond to species. For example: dogs are a sub-species of wolf; but the word "deer" refers to a family of 34 species, such as the red deer and mule deer.

Abbreviation

Books and articles sometimes intentionally do not identify species fully and use the abbreviation "sp." in the singular or "spp." in the plural in the place of the specific epithet, for example Canis sp. This commonly occurs in the following types of situation:

The authors are confident that some individuals belong to a particular genus but are not sure to which exact species they belong. This is particularly common in paleontology. The authors use the "spp." as a short way of saying that something applies to many species within a genus, but do not wish say that it applies to all species within that genus. If scientists mean that something applies to all species inside a genus, they use the genus name without the specific epithet. In books and articles which use the Latin alphabet, genus and species names are usually printed in italics.