Linnaeus's Last Stand?
cthompson at SEL.BARC.USDA.GOV
Fri Mar 30 09:37:16 CST 2001
Liz Pennisi has now formally declared in Science (23 March issue, pages 2304-2307) that we are again at war with ourselves. She quotes Mike Donoghue as saying people are *willing to throw down their lives!* over this, but she misses the whole point. This is clash of *have* and *have not* for everyone perceives that there is a finite money-pot for systematics. Where should it be invested, in knowing more about what we already know well (Phylocode camp) or in learning more about what we don*t know well (inventory camp (ALL, ATBI, etc.)).
Consider the history of *paradigm* shifts in a well-known group like birds. The first hundred or so years was invested in discovering new species. Collectors spread out from Europe to the far corners of the World finding new species, which American & European taxonomists described using Linnaean nomenclature (the native people already had names for their local species!).
Eventually most were named (and some named many times), so essentially species taxonomy was at an end. Fortunately, Darwin had by then proposed his theory of the origin of species (evolution), and the subspecies program was created, for to truly understand evolution one needed to study populations, and, therefore, they needed names. Hence, the race began again to describe new subspecies. This was great for Ornithology as it justified continued collecting, building larger collections, more curators, etc. And as all the obviously different populations were named, one merely collected more, longer series and divided the species even more finely, using statistics, etc. Unfortunately, in the 1950s Brown and Wilson spoiled the party, revealing to all the meaninglessness of the subspecies concept.
So, the *paradigm*(focus) shifted to higher categories, macroevolution, etc. Hennig*s principles were discovered to provide useful tools to divide up old para and polyphyletic groups. And what was being studied, the clades/groups had to have names. In the beginning that was easy, but as more new groups were discovered and named, it was also realized that the Linnaean system would only support a finite number of categories, that there is a limit to the number of new genera, tribes, families, etc., that one can name for a couple thousand species of birds.
So, the phylocode was invented as it better matches the needs of this new *paradigm.* Obviously as a new system, the old can be re-labeled as new, but even better each and every node on a cladogram can have it own name. And given the number of trees generated by numerical cladistic analyses, the number of nodes that can be named is almost infinite. Clearly the PhyloCode is superior to the Linnaean nomenclature.
Systematics doesn*t have Nobel prizes, but people can be remembered as the author of names of things (and that is why both codes have priority). So, naturally as groups became better known, what was being named shifts from *species,* to *subspecies,* to *higher categories,* and now to nodes of clades. Names are how systematists announce their new discoveries and how they recognize accomplishments.
For entomologists with millions of new species to be described, the Linnaean system is great, useful, and the challenge is to inventory the species we have not yet named. We worry about losing taxonomists, about ever getting the resources needed to complete our inventory of species.
But for those who work on well known groups (birds, butterflies, and flower plants), the focus is on REAL science, macroevolution, the relationships among those already described species. So there is a need for a new system, so that they can name new things (clades, nodes, etc.) and be recognized, etc.
And as David Hull would probably note, what better way to get exposure for your program, to get into Science, etc., than to declare a *paradigm shift,* in which your side is winning. Unfortunately, we, systematists, are again losing as we continue to fight among ourselves, not recognizing that we need a balance. We need to have species inventory, to expand Linnaean system, etc., which are critical goals for the little known creatures, from fungi to the bugs, but also important is knowing more about the relationships among those better known taxa (especially among *humans,* read Nature, not Science).
Oh, well ... it is going to be an interesting weekend in Washington.
F. Christian Thompson
Systematic Entomology Lab., ARS, USDA
Washington, D. C. 20560-0169
(202) 382-1800 voice
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cthompso at sel.barc.usda.gov
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