Naming a newly discovered animal species is governed by international rules, ensuring every organism has a unique and universally recognized identifier. This standardized system, known as binomial nomenclature, moves beyond local or common names that vary wildly by region and language. By providing a single, consistent name, the scientific community can communicate about a specific species without confusion, which is essential for organizing the vast diversity of life.
The Structure of Binomial Nomenclature
The scientific name assigned to any animal species is composed of two parts, a system formally introduced by Carl Linnaeus in the 18th century. This two-part name is called the binomen, consisting of the genus name followed by the specific epithet. When written, the entire binomen must be rendered in italics or underlined if handwritten, distinguishing it immediately from surrounding text.
The first word, the genus name, is always capitalized, functioning much like a surname that groups closely related species. Conversely, the second word, the specific epithet, is always written in lowercase letters. For instance, in the name Homo sapiens, Homo is the genus, and sapiens is the specific epithet.
Beyond the two core elements, a full scientific citation often includes the name of the author who originally described the species and the year of the formal description. This author and date, known as the authority, is typically appended without italics or parentheses, such as Panthera leo Linnaeus, 1758. If the species is later moved into a different genus, the original author and date are placed in parentheses, indicating a taxonomic reclassification has occurred.
Mandatory Steps for Validation
For a proposed scientific name to become officially recognized and available for use, it must strictly adhere to the requirements set forth by the International Code of Zoological Nomenclature (ICZN). The first mandatory step involves providing a definitive description or diagnosis of the new species. This description must clearly detail the features that differentiate the newly proposed species from all previously known relatives, establishing its uniqueness.
A proposed name must also be physically anchored to a real-world specimen, known as the type specimen. The most important is the holotype, a single physical specimen designated by the author as the official name-bearing type. This specimen serves as the permanent reference point for the scientific name and must be clearly labeled and deposited in a recognized, publicly accessible scientific collection, such as a major museum or university repository.
Finally, the description and the new name must be published in a way that ensures a permanent, public scientific record. This involves publication in a peer-reviewed, widely distributed scientific journal or comparable work obtainable by the scientific community. These procedural hurdles transform a proposed name into a valid, legally recognized identifier within zoology.
Principles Governing Name Selection and Stability
When selecting the actual words for a new scientific name, the author must ensure the names are either Latin or treated as Latin, regardless of their original derivation. This practice of Latinization is a fundamental linguistic requirement, rooted in Latin’s historical role as the universal language of science. The names should also be distinct, euphonious, and not easily confused with existing names for other taxa.
A core mechanism for maintaining long-term order in nomenclature is the Principle of Priority. This rule dictates that the valid name for any given taxon is the oldest available name that was properly published according to the rules. If multiple different names—synonyms—have been applied to the same species over time, the earliest one takes precedence.
The Principle of Priority favors historical precedence, preventing unnecessary changes to established names when new classifications are proposed. While the oldest name generally wins, the ICZN allows for exceptions to prevent confusion, sometimes permitting a more widely used junior name to be conserved over a long-forgotten senior name under specific conditions. This balance between strict chronological priority and practical stability keeps the system functional across centuries of discovery.