Furthering the divide has been dispute over whether molecular analysis belongs in taxonomy at all. For example, DNA bar coding—in which biologists use specific genetic markers to distinguish between species—has been criticized by many taxonomists as an unreliable replacement for traditional methods. The bias in botany, not without foundation, questions the reliability of plant DNA markers, which pose challenges not found in animal genome sequences. For one thing, finding dependable markers in plant genomes is especially complex. Efforts to pinpoint a plant bar code have yielded two markers with about 70 percent discrimination success between species. By contrast, a single marker used to bar code animals has 95 percent discrimination success. Yet as molecular analysis becomes more sophisticated and less expensive, its acceptance has grown. Already, basic genetic sequencing in the field has become possible through portable kits. And botanists who are embracing the change hope that DNA extraction will bring new life to herbaria, which are treasure troves of plant samples that could hold centuries-old botanical secrets, such as the heritage or identity of new species.
The opportunity for a change in taxonomy came with an alteration to one of botany's most notorious naming rules: Until January 1 of this year, the International Code of Botanical Nomenclature stipulated that any new species include a "diagnosis," or brief statement identifying how this species differs from any other—written in Latin. The IBC finally decided to drop the requirement, instated in the 1930s but harkening back to the 18th-century father of taxonomy, Carl Linnaeus.
In the case of B. plowmaniana, it was Renner who made the bold suggestion of including the molecular analysis where the traditional Latin diagnosis would had been. Thanks to Nee's detailed description, the paper still included all of the typical components—physical description, geographic distribution and place in the family tree—of a new species discovery, in English. With the collaboration of both traditional field botanists and a molecular biologist, the authors hope that the B. plowmaniana discovery is the first of many papers—and future species discoveries—that build on botany's dual strengths.
"This is the bringing together of two cultures," Renner says. "There has been so much discussion of bar coding and genetics, and initially so much skepticism. But now it is definitely the way of the future. Not to replace one or the other side of botany, but to use both."