Scientists have identified a new species of pint-sized humans, Homo floresiensis, that apparently flourished on a small Indonesian island some 13,000 years ago. What's the process for getting a newly discovered species recognized as a legitimate member of the animal kingdom?
The process is rather decentralized, as there is no international body that decides whether a new species is truly distinct from other members of the same genus. Instead, the decision is left primarily to the editorial boards of peer-reviewed biological journals, where research on new species must first be published in order to gain widespread acceptance in the scientific community. The Homo floresiensis find, for example, was first announced in the pages of Nature, one of the world's most prestigious peer-reviewed journals.
That isn't to imply that discovering and verifying the existence of a new species is an easy task. The specimen must be compared to as many other members of the genus as possible, to confirm the uniqueness of whatever attributes supposedly qualify the animal as a new species. When possible, the specimen is compared directly with holotypes, or the exact specimens that were used to identify species discovered previously. In practical terms, this can mean months of studying remains in a university museum or sifting through thousands of journal articles in the Zoological Record, an animal biology database containing papers dating back to 1864. (Once a journal article describing a new species has been added to the Zoological Record, the species can be said to have truly arrived.)
Once the researcher is confident that his find is, indeed, a new species, it's time to select a scientific name for the critter. Scientists must follow the guidelines of the International Commission on Zoological Nomenclature, the London-based organization that oversees all zoological naming regulations and adjudicates disputes. The ICZN's 306-page code lays down all the rules on what constitutes an appropriate name, as well as how it must be published initially. For example, the journal within which the name is first revealed must be available for either gift or purchase, so doctoral dissertations don't count. The first mention of the name should be followed with a special notation, to indicate that it's in reference to a new species. And a name can be ruled invalid if it appeared publicly before making its official debut in a peer-reviewed journal.
But the discoverer is given significant leeway to choose a name with some flair. Homo floresiensis, for example, is a reference to Indonesia's Flores Island, where the remains of the species were unearthed. Other researchers, however, use the occasion to pay homage to personal heroes. One entomologist named a species of owl louse Strigiphilus garylarsoni, as a tribute to The Far Side cartoonist Gary Larson, who is known for his humorous depictions of bug hunters.
The Homo floresiensis is a landmark not just because it sheds new light on human evolution, but also because the discovery of new mammalian species is a relative rarity. Of the 1.7 million species names acknowledged by the ICZN, only about 5,000 belong to mammals. When a new mammalian species is occasionally discovered, it's usually something a lot less exciting to the layman, such as a giant rat. New insect discoveries are much more common—in one national park in Tennessee alone, dozens of new species of moths have been discovered over the past several years. The oceans, too, are yielding an amazing amount of newly discovered animal species: The 10-year Census of Marine Life may yield over 20,000 new fish species by the time it ends.
Explainer thanks John Pickering of the University of Georgia.