Skepticblog

The spectacular skull and jaws of the extinct Miocene peccary Skinnerhyus shermerorum, on display in the fossil mammal hall of the American Museum in New York.

What’s in a name? A rose by any other name would smell as sweet
—William Shakespeare, Romeo and Juliet

The science of classifying organisms is known as taxonomy (Greek, “laws of order”); any named grouping of organisms (a species, a genus, etc.) is called a taxon (plural, taxa). Deciding how to name a new species and genus may seem to be a highly specialized, legalistic dimension of biology and paleobiology, not nearly as glamorous as ecology or behavior or physiology. But taxonomy is not just naming species, because species and higher taxa reflect evolution. Taxonomists do much more than label dusty jars in a museum. They are interested in comparing different species and deciding how they are related and ultimately in deciphering their evolutionary history. They look at the diversity of organisms in time and space and try to understand the large-scale patterns of nature. They look at the present and past geographic distributions of organisms and try to determine how they got there. In short, they look at the total pattern of natural diversity and try to understand how it came to be. Contrary to stereotypes, they are among the most eclectic of biologists and paleobiologists.

All these various enterprises go beyond conventional taxonomy and are usually given the broader label of systematics. Systematics has been defined as “the science of the diversity of organisms” (Mayr, 1969, p. 2) or “the scientific study of the kinds and diversity of organisms and of any and all relationships among them” (Simpson, 1961, p. 7). Its core consists of taxonomy, but it also includes determining evolutionary relationships (phylogeny) and determining geographic relationships (biogeography). The systematist uses the comparative approach to the diversity of life to understand all patterns and relationships that explain how life came to be the way it is. Put this way, systematics is one of the most exciting and stimulating fields in all of biology and paleobiology.

Taxonomists and systematists may not be as numerous or well funded as molecular biologists or ecologists or physiologists or behaviorists, but their labors are essential. All other disciplines in biology and paleobiology depend upon taxonomists to give their experimental subjects a name and, more importantly, to give them a comparative context. If a physiologist wants to study the organism that is most like humans, it is the taxonomist who points to the chimpanzee, our closest evolutionary relative. If an ecologist wants to understand how a particular symbiotic relationship may have developed, or the ethologist wants to understand a peculiar type of animal behavior, they need to know the evolutionary relationships and phylogenetic history of each organism, and these are the domain of the systematist. Systematics provides the framework of understanding and interconnection upon which all the rest of biology and paleobiology are based. Without it, each organism is a random particle in space, and what we learn about it has no relevance to anything else in the living world.

In our present age, taxonomists have become scarce as grant funding dries up and students go into more glamorous specialties that require big, expensive machines. Yet one of the most important issues on this planet today—biodiversity—is within the domain of systematists. Without someone to describe, name, and count all the species on this planet, how will we know whether we are wiping them out catastrophically, or whether they are holding their own, or even flourishing? Without the perspective of past diversity changes on this planet, how can we decide the severity of human-induced mass extinction? Each time someone surveys a patch of rainforest, trying to determine how humans have impacted the life there, his or her first task is taxonomy. Ecologists complain that they cannot find anyone who has the right training to identify and to describe all the new species of insects and birds and plants that are being destroyed even before we get to know them. Without knowing that they are there, how can we decide how important they might be? One of these species might hold the cure to some deadly disease or the solution to the control of a nasty pest, but without systematic and taxonomic research, these species go extinct before we even encounter them.

In the context of paleontology, the situation is analogous. The public may think that collecting big dinosaur specimens in exotic places is exciting, but it is just a tiny part of paleontology. Collecting and preparing fossils is a specialized task, often performed by people with little advanced scientific training. Analyzing and understanding their taxonomy, geography, and phylogenetic relationships is the domain of the systematic paleontologist. Without a properly trained paleontologist to correctly identify, name, and analyze the fossils, they are mute stones. Hours in the laboratory and museum collections spent measuring and describing specimens may not seem as glamorous as visiting exotic places, but they are equally essential. From this naming and description comes the understanding of larger problems in paleobiology, such as: how is all life interrelated? What is the past history of life? How has diversity on this planet changed? Without the foundation of systematics, these questions cannot even be approached.

When Linnaeus and other early natural historians developed different schemes of classification, there was no general agreement on how it should be done. Linnaeus’ system became so successful that it soon became the standard in most parts of the world, but still there were no official rules, and chaos reigned. If one systematist didn’t like a particular name for an organism, he might rename it for no good reason. Another systematist might use a name that had already been used for some other animal. Still another might name the species in his native language or name the species after himself. Some taxa were given more than one name. Systematics became a battleground of natural historians squabbling over proper names, and there were no referees to break up the fights. To bring order out of this chaos, rules were needed. In 1842 Strickland proposed the first code for zoology. Over the years these codes have evolved, and the first international code of zoological nomenclature was published in 1905. The current International Code of Zoological Nomenclature (ICZN) was last revised in 2000 (available both in printed form and online).

Taxonomic codes of nomenclature have an important purpose: to enhance stability and improve communication when creating or using taxonomic names and making taxonomic decisions. Systematists around the world are bound to follow these rules if they want their taxonomy to be recognized by other scientists. If they fail to do so, their work may not be published because journal, and book editors follow the codes strictly. If systematic descriptions or new species are somehow published but do not follow the rules, they may be corrected by someone else who does follow the rules. At times, it seems that systematics becomes bogged down in legalistic trivia, but the rules are essential if taxonomists want to avoid unnecessary squabbles and wasted or duplicated effort. It is comparable to knowing the rules of the road before you take your driver’s test to get your license. The Department of Motor Vehicles doesn’t want you behind the wheel on the streets if you don’t know the rules that everyone else is following. Similarly, the international community of systematists avoids “collisions” and “mistakes” by following their own internal set of “traffic rules.”

Bound in bright green, the most recent edition (2000) of the ICZN runs to 306 pages, covering 90 articles and 86 recommendations, with the first 126 pages in English followed by a separate section in the equivalent French. (Except for the French, most international zoologists use English in international communication and publication.) The arbitrary starting point of the code is 1758, which is when the tenth edition of Linnaeus’ Systema Naturae was published. Names and taxa proposed before that date are not bound by these rules (but may not be recognized, either). The code is built around several basic principles.

A fundamental part of the process is binomial nomenclature (Article 5). These are the basic rules by which genera and species are created, named, and described. Each binomen (“double name” in Latin) must be based on Latin or latinized words from other languages to enhance international communication across language barriers. The latinized binomial is not always based on actual Latin words, but it must still follow the rules of Latin grammar. For example, if the species name is an adjective, it must be in the same gender (masculine, feminine, or neuter) as the genus name that it modifies. (Although few scientists know Latin these days, it is still useful in surprising ways.) The new taxon must be adequately diagnosed, described, illustrated, named, and published in a recognized scientific journal that is widely distributed and available to most systematists. This does not include unpublished dissertations and local newsletters with limited circulation. In addition to a clear definition and description, the author must also indicate the geographic or stratigraphic range of the taxon and list any relevant measurements or statistics. The origin and meaning, or etymology, of the new name, is also usually indicated (although this is not required). You can base names on any word as long as it is properly latinized, except that you cannot name a taxon after yourself. (You can, however, name it after a friend, and have your friend do the same for you with a different species.)

I had just such an opportunity in the past few years, as I’ve been working on a complete revision of the extinct North American peccaries, family Tayassuidae. Known as “javelinas,” these pig-like creatures are exclusively a New World group found mostly in Central and South America. Despite appearances, they are not that closely related to the Old Word true pigs, or family Suidae. After I completed 25 years’ worth of work revising North American rhinos in 2005, I moved on to peccaries because there were hundreds of undescribed new specimens accumulated in the past 70 years in the American Museum collections. The last person to work on them did so 20 years ago, with most of his work remaining in his unpublished dissertation; he has since dropped out of the profession. Yet among all these new specimens are many incredible new skulls and skeletons that are surely new species and genera. In my spring 2011 historical geology class at Occidental College, I had two outstanding students who wanted to work on some kind of paleontology project with me, and both were interested in helping with these peccary projects. I made arrangements to meet one of these students, Audrianna Pollen, up at UC Berkeley, where we spent hours studying and describing this new species from the late Miocene Blackhawk Ranch locality near Danville, California. I met the other student, Jessica Grenader, at the American Museum in New York, where she worked on the most primitive known species of the Ice Age flat-headed peccary, but from beds almost 7 million years old. Those research trips in spring and fall 2011 finally bore fruit: after the usual publication delays, both of their papers finally came out late in 2012. As we had agreed when we started years earlier, Jessica and I named the new flat-headed peccary Platygonus pollenae, and Audrianna and I named the new Blackhawk species Woodburnehyus grenaderae.

In addition, there was another closely-related peccary already on display in the fossil mammal hall of the American Museum with the incorrect and outdated name “Macrogenis crassigenis.” I could tell at a glance that this amazing skull, with its spectacularly flaring cheekbones, was no Macrogenis, but a new genus and species. No one had done the necessary analysis to demonstrate this, or formally published a new name for this specimen, so the Museum had used the best available published name for a related species. But with our paper on Woodburnehyus grenaderae, there was an opportunity to finally name and formally describe this amazing fossil as well. Audrianna and I agreed that we would name it Skinnerhyus shermerorum, in honor of the famous paleontologist who collected it (Morris Skinner) and in honor of our friends, Michael and Devin Shermer. (Audrianna and Devin had been close friends and roommates in college, and both were in that same historical geology class together).

Pat Linse’s restoration of Skinnerhyus shermerorum, showing the bizarre flaring cheekbones (comparable to those seen in some fossil and living pigs, such as warthogs)

So, at the Skeptic Society meeting on Dec. 16, 2012, Pat Linse (who had done the illustrations of the fossil for our publication) and I made a formal surprise announcement of the publication of Skinnerhyus shermerorum, and we printed out special T-shirts for the occasion. Michael Shermer may have earned a bunch of accolades and awards and honorary degrees over the years, but only a handful of people alive have such a spectacular fossil named after themselves!

Postscript: I too have a fossil named after me: a huge primitive rhinoceros from beds about 40 million years old in central Oregon was named Zaisanamynodon protheroi by my colleague Spencer Lucas (it’s on display at the John Day Fossil Beds Visitor Center, if you happen to visit). So the next peccary I get to name will be named lucasi to honor him.