MODULE #1: Biology: The Study of Life
Naming Organisms Based on Classification
Of course, with a more complicated key, you could continue your classification of an organism right down to species. Why bother? Well, as we said before, classification is a way of ordering the diverse data in biology into some reasonably understandable system. This is such an important practice that an entire field of biology is devoted to it. We call this field taxonomy
(taks ahn' uh mee).
Taxonomy – The science of classifying organisms
Taxonomy is a very important part of biology because, in order to give a scientific name to an organism, we must know both its species and its genus. In biology, we name things with binomial (bye no' mee ul) nomenclature (no' mun klay chur).
Binomial nomenclature – Naming an organism with its genus and species name
People, for example, are called Homo sapiens. Homo is the genus to which humans belong, and sapiens is the species. Notice that in binomial nomenclature, we italicize the genus and species name. This is to emphasize that we are using binomial nomenclature. In fact, whenever we use a genus or species name alone, we still italicize it, just to emphasize that it is a part of binomial nomenclature.
So, in order to properly name an organism, we need to know its genus and species. For example, if you were classifying oak trees, you would find that all oak trees are in genus Quercus. A red oak is given the species name rubra, while a white oak is given the species name alba. Notice that while we have capitalized all classification names up to this point, we do not capitalize the species name. This is a convention that makes binomial nomenclature a bit clearer. Thus, the scientific name of the red oak is Quercus rubra, whereas the scientific name of the white oak is Quercus alba. As a point of notation, once we have introduced a genus name, we are allowed to abbreviate it in discussions that follow. Thus, we could say that the red oak is Q. rubra and the white oak is Q. alba.
Now why bother to do this? Why not just call a white oak a white oak and a red oak a red oak? Wouldn't that be easier? Well, yes and no. You see, English is constantly changing. What we mean by “oak” today may not mean the same thing in 100 years. That's because a spoken language continues to change. Latin, however, is a dead language. It will never change. Since a lot of binomial nomenclature is based on Latin, the binomial names of organisms do not change. Thus, Q. rubra will mean the same thing 100 years from now that it means today. Also, by using the genus name in the name of the organism, we have a start at being able to figure out other organisms that are similar to it. Any other organism that belongs to genus Quercus will be very similar to the red or white oaks. In addition, if we find out what family the genus Quercus comes from, we can find other organisms that are also similar to the white and red oaks. That's why we use this complicated naming system.