Species as "Hypotheses"
kinman2 at YAHOO.COM
Sun Jul 11 22:24:13 CDT 2004
Richard and other taxacomers,
Like many other things, I see a continuum of objectivity vs. subjectivity. 100% total objectivity (requiring 0% uncertainty) is unattainable, but we can certainly always increase the objectivity percentage by clearer thinking and increasing knowledge.
Add in the uncertainties of speciation as a continuous process, and there must be a HUGE variation in the objectivity possible in delimiting any particular species. My gut instinct is that the possible objectivity for circumscribing some species is probably very limited, and no doubt less objective than circumscribing some groups that are generally regarded as genera, or even higher taxa. If so, it is an exercise of needless frustration to argue that species taxa are necessarily more objective than generic or familial taxa. However, ON AVERAGE, I think species taxa are more objective than higher taxa, but the ranges of knowledge and objectivity are so great that NOT ALL species will be more objectively delimited than all genera, families, or even higher taxa.
The American robin as a species seems to be a pretty distinctive concept compared to many species of oak which are not nearly to that same level of species distinctiveness. Thus the "hypothesis" of the American robin as a species might approach the level of "a theory", at least compared to the hypotheses of circumscribing many species of oaks. But it is all matter of semantics that I often find very distracting, because I truly believe that future knowledge is going greatly alter our perception of what is objective. For example, the systematics of molluscs may be in for a significant "objectivity" (and nomenclatural) paradigm shift if bivalves are indeed basal to that group. Objectivity is clearly in the eye of the beholder, AS WELL AS the times in which he lives. And such shifting objectivity can often be strenuously resisted (e.g., that a bacterium, not stress, usually causes stomach ulcers, although that one was only controversial for about a decade).
That is just one reason why I am totally opposed to phylocode-type definitions of taxa at any level. Freezing definitions during any particular time and paradigm is short-sighted and arrogant, although it might be somewhat less so 50 years from now.
---------- Ken Kinman
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