THE BLOG
09/04/2013 01:52 pm ET Updated Nov 03, 2013

A Fish By Any Other Name

As far as I know, no fish has ever swam up to a person and said, "I am a bluefin trevally." Yet, it is in the very nature of human beings to classify and categorize, and thus we create names for things.

A report published earlier this year by Oceana brought much needed attention to the issue of mislabeled fish in our nation's restaurants and markets. Public health concerns, economic deception, and a possibility of fishery mismanagement were all discussed as ramifications of the level of mislabeling reported in this study. At the heart of the problem lies one central question -- what to call our fish.

It turns out, the names we use for fish are quite complicated, and depending on who we are and where we are, the names we use can be quite different. Fish on a menu are usually described by their English common names. Tuna, swordfish, and sea bass are menu items we are all used to seeing. The problem is, what is tuna? Are there more than one kind of swordfish? Is sea bass a family?

As you'll see in our latest video below, for fish on the coral reef, common names most often are in two parts, a modifier and a reference to the fish's family. The modifier sometimes denotes physical appearance: e.g. the teardrop butterflyfish is a type of butterflyfish that has a distinct marking on its side that resembles a teardrop shape. In other instances the modifier is taken from a behavior commonly observed: e.g. the rockmover wrasse is a wrasse species that is often seen picking up and tossing rocks about in its search for prey. The problem with common names is that there is no standardization in their use. One book or snorkeler fish ID card may denote a fish as a rockmover wrasse, while another book from a different author or in a different part of the world may call that same species a dragon wrasse (still an apt name as the juvenile of this species has a markedly different appearance from the adult form and resembles a dragon as it floats about hiding like a piece of algae).

Scientists long ago recognized the problem inherent in the common name system and established an internationally-standardized naming system to alleviate this confusion.

Scientific names take their origin from the work of Swedish botanist, Carl Linnaeus. In 1753, Linnaeus published Species Planturum -- the book that set the framework for what has become the modern classification system used by scientists for all living things. In this landmark work, Linnaeus described every plant that was known to him and gave each plant a two-part name consisting of a genus and a species. This system, known as binomial nomenclature, was useful to scientists as it helped organize things into groups of related organisms. Even though Linnaeus's work long preceded the work of Charles Darwin and the theory of evolution, he was aware of seeming similarities between different plants, and he thought it made sense to group species together based on these shared characteristics.

Fast forward 260 years, and scientists still use a naming classification system built off of Linnaeus's work, which now includes eight major taxonomic ranks:

Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species

The genus and species written together give each type of organism a unique name. For fish, the correct way to write these names is to capitalize the first letter of genus followed by lower case species name (all in italics) followed by non-italic last name of the scientist(s) who first described the species and the year in which the description was made. For example, the aforementioned bluefin trevally's scientific name is Caranx melampygus Cuvier, 1833. If changes in the classification of the species have occurred (and changes are quite common as our understanding of evolutionary relationships continues to improve), the author's name will appear in parentheses. Scientific names of fish are regulated by the rules of the International Code of Zoological Nomenclature which gives priority to the first published name a species is given in the scientific literature. These rules help ensure that each species has a unique name no matter where in the world it is being studied.

Pacific Island cultures' knowledge of fish often far exceeds that of even the most highly trained scientist or marine biologist. This knowledge is partly reflected in the naming systems many of these cultures use which most often reflects the importance of fish as food items. In many island languages, fish which are similar in appearance and behavior but which have little or no food value will often share a single name - even though islanders are well aware of the fact they are different fish. For example, in Hawaiian language the word kīkākapu is ascribed to no less than eight different butterflyfish species and one fish - the Hawaiian morwong - that bears very little relationship to the butterflyfish at all. Although they are eaten, butterflyfish do not comprise an important part of the food fish so this general name for many of them is all that is necessary. On the contrary, fish which are important food species may have many names for even a single species depending on their size or stage of development. For example, a general name of weke, meaning, "to open," is given to several goatfish species who, in adult form, take on individual names for different species. Weke 'ā, weke 'ula, weke nono, and weke pueo are all different species highly valued for their taste and whose behavior on the reef is quite different. The young of these species are all called by a different name, 'oama, meaning, "finger length," which further reflects the different behavior they have as juveniles and the method used to catch them (typically throw net versus spear for adult fish).

Perhaps the best example of a fish having different names based on its stage of development is the fish commonly known as the crimson jobfish which has four Hawaiian names based on stage of development. Next time the waiter at your favorite Hawaiian fish house tells you the special is a ginger and garlic sauce over a nicely sauteed 'ōpakapaka, you can put on your scientist's lab coat, stroke your beard in an intellectual manner, and know he is going to bring you a delicious Pristopomoides filamentosus (Valenciennes, 1830) that was slightly less than two feet long.

Dr. Craig Musburger is a marine biologist and Emmy Award-winning underwater cameraman. He produces UnderH2O, a web series for PBS Digital Studios that follows him and his team on adventures that showcase the natural beauty of the ocean world.

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