Wednesday, January 23, 2008

Might Makes Truth

I take several multi-layered hats off my pleated brow in respect to the International Code of Botanical Nomenclature. Back in 1994 they codified the byzantine business of naming plants.
Now this is a monumental task. As you may know, living things are represented in the scientific literature and texts in a hierarchical arrangement. This means that they are grouped in descending layers according to increasingly detailed criteria. The theory is that the arrangement reflects the evolutionary descent of the species. The arrangement, from general to specific, is as follows:

Kingdom, Division, Class, Order, Family, Genus, Species, Subspecies, Variety, Cultivated Variety, Form.

The codification looks to reduce or eliminate confusion and reckless habits in the taxonomic culture. As an example, take the orb-weaving spider. Its genus name is Pachygnatha and its species name is zappa. Zappa? Indeed, it is a tribute to the late Frank Zappa, the prolific electric guitarist of the Psychedelic Age of the mid-20th century. Evidently, a black mark on the spider was inspired by Frank's late mustache. The turmoil that results from such a designation can only be imagined. After all, the science behind the hierarchy is staid, peer reviewed, unyielding, unassailable, and dependable, and the scientific communities that surround it are stabilized by its influence. Open the nomenclature to guitarists, and who knows what vermin, vagrants, villians, and vagabonds will infiltrate the hierarchy. Imagine the pressure on simple postulates and theorems! Instability would result and cascade throughout the web of scientific disciplines. Who would want his name connected with collapse of ideas?

The scientific rationale of hierarchy, at a glance:
Species: One text defines it this way: "Ideally and theoretically is a set of individuals closely related by descent from a common ancestor. Members of a species can interbreed with each other successfully but cannot interbreed with individuals of any other species." Yes, there it is. Of course, the text continues, "Most species are not so predictable."
Subspecies: Here it states, "They may not interbreed well with closely related species but an occasional cross pollination results in a viable seed that grows into a fertile adult. If this occurs frequently, the two plant groups may best be considered subspecies of a single species." So there.
Genus: It continues, "Closely related species are grouped into genera. Deciding whether several species are closely related enough to be placed together in the same genus is difficult." Indeed. We have mathematical models that correct human error.
"No objective criteria exist; the decision is entirely subjective and often the cause of great dispute." Not to be alarmed: Scientific progress has come at great human cost. The human toll must be absorbed.
"Both groups of taxonomists agree that the two sets of species are closely related, but they have different opinions as to how much evolution has occurred since the time of the most recent ancestor."¹ This divergence of opinion creates another hierarchical branch, one of which leads to an intellectual dead-end, wherein scientists are isolated from their kind, and the other of which leads to sweeping biological glory and fame.
Variety: This is from the International Convention for the Protection of New Varieties of Plants: "Variety means a plant grouping within a single botanical taxon of the lowest known rank, which grouping, irrespective of whether the conditions for the grant of a breeder's right are fully met, can be defined by the expression of the characteristics resulting from a given genotype or combination of genotypes, distinguished from any other plant grouping by the expression of at least one of the said characteristics and considered as a unit with regard to its suitability for being propagated unchanged." Of course, clear reason tells us that one hierarchical level is preserved for economic integrity. No rational person would disagree with this. The survival of the investigator is essential to scientific progress, hence, intervention in taxonomic systems to preserve economic viability of keystone biologists is justified in this case. And we can state with a fair level of certainty that the anticipated adverse impacts of protected economic interests within the scientific method would be negligible or absent. Error reduction formulations are available to eliminate empirical data suggesting otherwise.
And it is understood, varieties can evolve into subspecies and subspecies can evolve into varieties, provided they are not economically viable or observed. This is verified by the observation that "Europeans tend to use subspecies and expect subspecies to occupy somewhat different areas whereas Americans use variety to denote plants that are different from the plants first put in the species. In practice, the two ranks are used almost interchangeably."² When economic viability is a concern, reclassification reverses the evolutionary process and preserves the investigator and thereby the community that supports him.
Thus, there is the possibility that, under extreme conditions, the non-competitive investigator may find himself mutating into a subspecies unless given protective status. In the absence of intervention, this has led to a disadvantageous condition, one that compels many scientists to flee the University settings and take refuge outside of the intellectual community, to dwell in shame and obscurity, reduced to mere shadows of men, thick-tongued brutes uttering maddening rhyme.
Form: "The rank of taxa below variety; the narrowest taxon; a plant which retains most of the characteristics of the species, but differs in some way such as flower or leaf color, size of mature plant, etc."³ At last! we reach the very bottom of living things, the point at which all scientists converge.
But wait. The Code states, "If a greater number of ranks of taxa is desired, the terms for these are made by adding the prefix sub- to the terms denoting the principle or secondary ranks. A plant may thus be assigned to taxa of the following ranks (in descending sequence): regnum, subregnum, divisio or phylum, subdivisio or subphyllum, classis, subclassis, ordo, subordo, familia, subfamilia, tribus, subtribus, genus, subgenus, sectio, subsectio, series, subseries, species, subspecies, vari-etas, subvarietas, forma, subforma."
And then, "The Code also requires that plant diversity be summarized in a hierarchical structure. Again it is not a question of whether such a structure really exists. the fact that the Code assumes the existence of a species and a hierarchical structure does not mean that the assumptions are correct, merely that, in naming plants one must act as if species are real and nature is hierarchical."²
History may write about the great Evolutionist Wars of the 21st century; the dynamic epoch when swarms of heavily-armed Darwinians battled one another on college campuses around the globe.
May the fittest scientist win!

¹ Mauseth, James D. 2003. Botany: An Introduction to Plant Biology. Jones and Bartlett Publishers, Sudbury, MA.
² Utah State University Herbarium
³ GardenWeb