Northwestern Fence lizzard

Our western fence lizard is Sceloporus occidentalis — "Sceloporus," a combination of "scelos" (Greek for leg) and "porus" (Latin for hole) — refers to the characteristic, pronounced pores on the legs of this genus of spiny lizards; "occidentalis" refers to western.

Contributed by Marty Giles

Every serious naturalist is quickly immersed in a sea of scientific names as he or she graduates to more technical resources. Although the foreign words may be intimidating at first, they become very useful and informative with a small amount of background information.

Nature Guide Journal

Marty Giles

The basic scientific name has two parts that together identify a species. A "species" is usually defined as a group of organisms related closely enough to allow successful interbreeding among members. “Successful” defined as bearing offspring that can, themselves, successfully breed.

Rather like listing a person's family name first, the first name in the set of two denotes the group one step up from individual species, the "genus." The second name in the set denotes the species within the genus.

Part of the beauty of using this double name system is that it illustrates the relationship between closely related species. For example, the dog genus, Canis, has several well-known species: Canis domesticus (the domestic dog); Canis latrans (the coyote); and Canis lupus (the wolf). The red fox, Vulpes vulpes, and the gray fox, Urocyon cinereoargenteus, are different enough to be in a different genera, Vulpes and Urocyon.

The words used in the naming are usually Latin or Latinized (sometimes Greek or Greek-influenced) descriptions of the organism, though sometimes organisms are named in honor of a person or place. Acer macrophyllum identifies a maple (Acer is the classical Latin word for deciduous tree) that has large ("macro") leaves ("phyllum") — "big-leaf maple." Acer circinatum is a maple with circular leaves — our vine maple. Acer japonicum is, of course, "Japanese maple."

Scientific names also eliminate confusion and ambiguity. In some cases, a single kind of plant or animal may have more than one common name ("cougar," "mountain lion," "puma," for example). In other cases, one common name may be used for many different species ("dandelion," for example). And, most species, counting those microscopic, have no common name at all. Using a scientific name clearly indicates a member of a particular species.

The names are authorized by widely accepted commissions or groups that evaluate the names and research on the relationships between species. Scientific names may change as our knowledge about a given species improves. The most common kind of change occurs when a species is deemed to be more or less closely related to other species in a particular genus, resulting in the genus name changing to another established genus or changing to a new, separate genus. In those cases, the species name stays the same.

The genus and species are just part of the overall taxonomy (the orderly classification based on relationship). Subspecies — notable groups within a species — are sometimes indicated (either spelled out, resulting in three words, or indicated by "ssp"), but higher levels of relationship are generally not part of the scientific name.

As a matter of form, scientific names are always in italics or underlined (rarely in bold type), and the first letter of the genus name is always capitalized. The species name is always lower case in the modern usage, though some still use the older practice of capitalizing the species if it’s based on a proper noun. The genus name is often given just by initial in a list of species in the same genus or if the genus has just been mentioned in the document, or (rarely) if the organism is very familiar — “E. coli” for Escherichia coli, for example.

Although it is certainly not the most important aspect of learning about a plant or animal of our world, the scientific name is a capsule of interesting and pertinent information about the organism. The precision, description, and demonstrated relatedness that come with using scientific names are ample reward for the effort.

This popular Nature Guide Journal column first ran in The World on Aug. 25, 2007.

For information on how you can arrange an exploration of our fascinating natural history, contact Giles at 541-267-4027,, or Questions and comments about local natural history are welcome.