Taxonomy is the source of much disagreement in biology. Many ecologists and physiologists don't even think it's important to know or be able to identify species, while taxonomists and systematists regularly insist that proper identification is the basis of all biological information.
I tend to side with the taxonomists on this one. Taxonomy itself (the basic classification of life forms into categories such as "family," "species" and "kingdom") is a rather invalid way of viewing biodiversity, but it is a necessary convention in order to enable better communication of information between researchers.
When speaking of the names of biological species, there are a number of conventions that biologists use.
For instance, each species is referred to by a binomial name consisting of a "generic name" and a "specific epithet" (example:
Tyrannosaurus rex). "Tyrannosaurus" is the generic name (name of the genus) and "rex" is the specific epithet (name of the species). Binomial names are always supposed to be written in italics (or underlined when written by hand).
Generic names are always capitalized. Specific epithets are not.
Binomials are often abbreviated by using only the first letter of the generic name and the full specific epithet. The proper format is
T. rex, not T-Rex or T-rex as is often written by the lay public.
A species epithet is never to be used in isolation, without the generic name either in full or abbreviated (although this rule is frequently violated). Example:
afarensis should be written:
Australopithecus afarensis or
A. afarensis.
Also of interest is that the common names of dinosaurs usually derive from their generic names (e.g., "
Triceratops" is both the generic name and the common name for
Triceratops horridus, and also for another species, "
T. prorsus," which may or may not be valid). One exception is
Tyrannosaurus rex, which, for whatever reason, lay sources insist on referring to by the full binomial, without realizing that they are violating basic requirements of parallelism in writing and presentation by not also calling "Triceratops" by its full binomial.
This is, of course, relatively harmless when it's just used for kids' books and toys, because the non-systematic approach for kids' products is sufficient to fill the kids' needs to choose their favorite dinosaur and play games with their friends.
But, for scientists, more rigor is generally needed (particularly for living organisms), and I must insist that the concept of species (whatever definition you feel is most valid) is absolutely critical for the sake of communication among scientists, despite the inherent kinks, hitches and constant revisions that the system must undergo.
Sorry for the rambling, but I felt like it was important to at least make sure people were aware of conventions, even if you don't care and don't intend to follow them: just so long as you know they are there and that they do have a purpose in science.
Edited by Bluejay, : superfluous quote
-Bluejay (a.k.a. Mantis, Thylacosmilus)
Darwin loves you.