A prominent tropical ecologist—who will remain nameless, to protect the guilty—asserted that taxonomy is something that you do once. In his view, after a species is named the work of taxonomy is done and we can get on with truly important science, like ecology. He was wrong on two counts.
First, species are not named once for all time. Species, at least when they are scientifically credible, are hypotheses, not pronouncements. As such, they make predictions about combinations and distributions of characters and are, like any other hypothesis, subject to testing and possible refutation. Second, taxonomy is not the mere labeling service that he implied. It is as intellectually challenging, rewarding, rigorous and impactful as any other science. In order to be reliable, to remain relevant and informative, taxonomy cannot be done once and forgotten. It, like any science, is a continuing process of discovery, an ongoing quest for knowledge that has no end.
Figure 1. Map of the island of Utopia. A woodcut by Ambrosius Holbein, in 1518 edition of Sir Thomas More’s Utopia.
In an opinion piece published in Nature in 2001, Nimis highlighted the tension that exists between “Name-users,” like our ecologist friend, and name-givers or “Real” taxonomists. Name-users want species designations that are unchanging. That is possible only if we sacrifice the assurance of credibility and accuracy. To be reliable, names must be free to change as hypotheses are tested and new evidence is found. Gene Gaffney put it succinctly: nomenclatural stability is ignorance. Those who call for unchanging names are, in effect, advocating for ignorance over knowledge which is as much a disservice to name-users as it is an affront to science.
Only with perfect knowledge could our ecologist’s idea of nomenclatural utopia exist: a world in which every species has a unique, never-changing name. This version of utopia is fantasy, not science. Some ecologists mistakenly see species as occurrence data, like measures of annual rainfall—but species are not so easily accounted for. While species do exist in nature, may be identified, and their presence or absence noted, they are nonetheless hypotheses. As such, their reliability and stability depend on how thoroughly and repeatedly they are tested. Some common species have been extensively corroborated, such as the house fly, Musca domestica. Many others have been less frequently put to the test. And, as stable as our conception of the house fly has proven to be, knowledge of this species is never absolute. The next observation, the next specimen observed, has the potential to falsify the hypothesis “house fly” as it currently exists.
Nimis favored getting rid of Linnaean binomials, the combination of genus name and specific epithet, and replacing them with single-word names. Uninomials, he suggests, would avoid the inconvenience that ensues when a species is moved from one genus to another—and its binomial changed accordingly. This does not obviate the need for testing, however. Said another way, names would still be subject to change. Moreover, binomials communicate information that would be lost with uninomials. Quercus alba, for example, tells me that the species in question is the white oak. The fact that it is assigned to the genus Quercus tells me which, among hundreds of thousands of flowering plants, are its nearest relatives. Binomials signify unique combinations of characters at both the specific and generic levels and are almost always accompanied by at least some geographic, ecological or natural history information. All useful stuff to know; a good deal of which are lost with a single-word name.
Misunderstanding the mission of taxonomy, many ecologists denigrate it as “stamp collecting” and fail to support positions and funding for taxonomists. They are now paying the wages of this particular sin. The reason that species may not be readily identified, reliably called by name, or enjoy the relative stability that comes with corroboration of hypotheses is that there are too few taxonomists to create and verify knowledge. It may be tempting to blame taxonomists for the dearth of knowledge and names, but they did not volunteer to have taxonomic jobs and funding eliminated. Those were decisions made by colleagues and administrators and the steady homogenization of biology as experimentation.
The most efficient way to test species hypotheses is to simultaneously consider evidence for all species of a monophyletic higher taxon, such as a genus or family, in a revision or monograph. Far from “merely descriptive,” such studies are the gold standard for formulating and truthing our ideas about species, characters and relationships. In hyper-diverse taxa, like many families of insects and flowering plants, revisions were historically completed only one or a few times each century. With the current neglect of taxonomy, their frequency is further declining, along with the availability, reliability, and stability of names.
The solution is not changing rules for names or substituting DNA barcodes for more informative evidence, it is more taxonomy. If we want species to be identifiable and to correspond to actual entities in nature; if we want abundant information about them; if we want names to be as stable as they can be made, then the solution is as simple as it would be effective: educate, employ and support taxonomists and the growth, development, and constant use of collections. Anything less, any shortcut, any end-run, any technological surrogate, will result in less reliable, less informative results.
Nomenclatural utopia for the taxonomist looks much like the status quo, but better supported: a world in which names are linked to explicitly testable hypotheses, in which species are continuously tested by collecting and observation, in which species are vouchered with museum specimens, and in which all relevant sources of evidence are synthesized in analyses and classifications. If species are to be credible scientific concepts, then there are no quick fixes, no simple changes of rules, no technologies that can replace critical thought and the weight of objective evidence. Credible species and stable, informative names are the result of credible taxonomy.
As a taxonomist, I have deep respect for ecology and ecosystem science. Sadly, such respect is not mutual. Advances in our understanding of the biosphere, from species interactions to ecosystems functions, have increased our appreciation for the amazing organization of life on our planet, the critical connections among living things, and the fragility of it all. Rather than recognizing taxonomy as a window into diversity at and above the species level, and into evolutionary history, many ecologists see taxonomy as no more than a source of identifications and names.
Perhaps most importantly, the inconvenience of name changes draws attention to an inherent conflict between environmental scientists and taxonomists. The environmental sciences are experimental and contemporary. Taxonomy, in contrast, is comparative, observational and historical in perspective. Environmental experiments produce a universe of outcomes so muddled that statistical gymnastics are needed to determine whether a particular outcome is significant. Most taxonomic hypotheses are far more elegant all-or-nothing claims. All spiders have spinnerets; all angiosperms have flowers. You need only observe a single spider without spinnerets, or a flowerless angiosperm, in order to falsify this prediction. This is the epitome of rigor in science, so it is ironic that ecologists look down upon it.
Environmental biologists want scientific names to be immutable data points as they monitor the presence or absence of organisms in ecosystems over time; taxonomists want names to be notations for hypotheses that are open to potential refutation. It is impossible to have both. Either names are arbitrarily made immutable and run the risk of ceasing to correlate with our best knowledge of what exists in nature, or they are subject to change in order to remain reliable reflections of current knowledge and evidence.
Environmental biologists wish to learn how living systems function and change through time, and do not want to be distracted by changing species names. Their goals are hugely important, but wishing for immutable names works against, not for, them. In contrast, taxonomists want to know what kinds of living things exist, what makes each unique, how they are related, and the sequence of character transformations responsible for their diversity. These are equally important goals. Goals that require that names change as knowledge grows.
These aims are so different that no simple solution can satisfy both. A good starting point is to recognize and respect these differences, then seek ways in which the growth of taxonomic knowledge may be made less inconvenient to ecologists. The answer is not to change how taxonomy is done; nor is it to simply tell ecologists to suck it up. I believe the answer will come from information scientists. A sophisticated information system capable of both tracking the growth of taxonomic knowledge and treating it, and associated name changes, as metadata largely invisible to the casual user of names. Innovative steps in the right direction are already underway (see, e.g., Pyle 2016 and Sandall et al. 2022).
Those who decry how difficult it is to identify species and call them by name have blood on their hands. Most stood by silent, or were active participants, as positions for, and grants supporting, taxonomists were eliminated. For decades, experimental biologists, including most ecologists, have misrepresented, through ignorance, malice, or both, the science of taxonomy. Now, after years of neglect and antagonism, they have the audacity to blame taxonomists for the lack of information and instability of names.
Taxonomists do not call on ecologists to abandon their scientific aspirations or standards to supply autecology information about the species they study. Ecologists are appropriately engaged in pressing issues facing their own science. It would be scientifically counterproductive to reduce ecology to a mere service. We need and want ecology as an independent science to understand the biosphere. We should expect no less of taxonomy.
I did not become a taxonomist because it’s results are useful to others, but because it is fantastically interesting and exciting to explore the diversity of species and characters, and their evolutionary-historical origins. I do, of course, appreciate that taxonomic knowledge is so impactful on biology and society. And, while applied knowledge of species more than justifies support for taxonomy, as a fundamental science it is so much more. It would be calamitous to make either taxonomy or ecology subservient to the needs of the other. Each are best served when the other is pursued for its own sake, to its own high standards, with resulting knowledge shared freely.
Those who have an ecological world view are understandably exited by the potential of DNA barcodes to do an end-run around labor-intensive taxonomy and Linnaean nomenclature. But they should be careful what they wish for. Limiting data to DNA sequences has only the most superficial resemblance to the grand traditions of taxonomy, and it would result in vastly less knowledge. Of course, it is possible to lower standards, focus on the needs of users, and arbitrarily designate a stable set of names. But this would be a disservice to science. Ecologists should want more than stable names; they should want names that are accurate reflections of the kinds of living things that exist. The choice is excellence versus expedience; stability versus truth; ignorance versus information; and static versus up-to-date knowledge. We should heed Forest Gump who reminded us that stupid is as stupid does.
Taxonomists respect ecology and related sciences, recognizing that each has an important part to play in advancing human understanding and in confronting environmental problems. For a complicated set of reasons—including a failure of college curricula, undue influence of technology, fads in funding, experimental bias, and social interactions sadly reminiscent of cliques in middle schools across the country—experimental biologists are unwilling to take the time to understand the scientific rigor, goals and methods of taxonomy. They are so narrowly and selfishly focused on their own immediate needs that they would sacrifice the grand, impactful goals and traditions of taxonomy in order to meet them. They naively confuse experiments with the scientific method. And they continue to malign and marginalize taxonomy, failing to recognize that their bias and greed are root causes of the dearth of scientific names.
Shortcuts, like DNA barcodes, are not the answer. Nor are less informative, less memorable, less easily communicated, arbitrary species identifiers. The answer is not to find a substitute for rigorous taxonomy or a way around its requirements for excellence. The answer is to acknowledge that neglecting taxonomy has been a colossal mistake, to change course, and to put the same energy into a taxonomic renaissance that is being wasted on a search for quick fixes.
There is good news for those willing to see it. Things are dire, but they’re not hopeless. Advances in taxonomy and technology create the opportunity to instantly modernize taxonomy’s infrastructure and accelerate its mission to explore, discover and make known species and history. Taxonomists have everything they need for an immediate revival of their mission, for completion of an inventory of earth species in a matter of decades, for creating an informative knowledge-base for all living things, for making natural history museum collections representative of the full diversity of life, and for elevating humankind by deepening our understanding of who we are as a species, and how we are related to other kinds of living things.
Taxonomy cannot succeed in its goals if it is measured by demands of ecologists any more than ecology could succeed if reformed to meet the needs of taxonomists. We need mutual respect and support, recognition that the environmental sciences and taxonomy are and should be complementary, neither subservient to the other.
Ecologists are motivated to understand how the biosphere works today. Taxonomists are primarily driven to understand what species and characters exist as a result of transformations in the past. Both perspectives are necessary in order to fully understand biodiversity, but they require very different approaches. Rather than compromising one to meet needs of the other, we must strive for excellence in each, and seek ways in which to more efficiently share information between them.
The object should not be to change either how taxonomy is done or the expectations of name-users, but to leverage information systems to meet the needs of both. Sophisticated software should be able to track complex changes in taxonomic concepts, names, and synonymy, while, at the same time, delivering a user-friendly interface for those, like ecologists, who simply want to use the correct names. This, of course, requires that we fund collaborative work between taxonomists and information scientists rather compromising scientific excellence with quick fixes.
References
Forest Gump. 1994. Movie, starring Tom Hanks, directed by Robert Zemeckis, distributed by Paramount Pictures.
Gaffney, E. 1979. An introduction to the logic of phylogeny reconstruction, pp. 79-111 in J. Cracraft and N. Eldredge, eds. Phylogenetic Analysis and Paleontology. Columbia University Press, New York.
Lapp, H. et al. 2011. Organizing our knowledge of biodiversity. Bulletin of the American Society for Information Science and Technology 37:38-42.
Nimis, Pier Luigi. 2001. A tale from Bioutopia. Nature 413: 21.
Pyle, R. L. 2016. Towards a global names architecture: the future of indexing scientific names. ZooKeys 550: 261-281.
Sandall, E.L. et al. 2022. A globally integrated structure of taxonomy supporting biodiversity science and conservation. Trends in Ecology & Evolution 38: 1143-1153.