Real taxa => Ranking

Ken Kinman kinman2 at YAHOO.COM
Wed Sep 29 22:41:03 CDT 2004


Richard (and other Taxacomers),
     Yes, it is evident which philosophical camp you are in.  However, I wouldn't say your postings have burdened the list.  On the contrary, your philosophical leanings seem rather Ashlockian, and many (including myself) find them to be a breath of fresh air.  :-)

      Those who have simplistically (and RELENTLESSLY) driven toward the goal of total paraphyly elimination for over three decades have not only ignored stability and usefulness, but have also ignored the underlying subjectivity of their own premise (that paraphyly is unnatural and thus unscientific).  Thus, Malcolm McKenna's classifications of mammals over the years have introduced so many new Linnaean intermediate ranks that he himself seems to now be in favor of abandoning ranked classifications.  It seems to be pretty clear that it is those who have abused Linnaean ranks that eventually want to abandon them when such abuse renders them almost useless.  It is the ABUSE that should stop, not the USE of ranks.  The abusers are blaming the victims instead of their own subjective rejection of paraphyly as a NATURAL part of the evolutionary process.   And of course, a PhyloCode which would MANDATE the subjective rejection of paraphyly makes this subjectivity even more glaringly apparent (perhaps the reason the PhyloCode makes many of the older strict cladists so nervous).

     As for Peter Stevens' hope that a more robust phylogeny of flowering plants could eventually allow basing ranks on absolute age, I had a similar reaction to that of Robin Leech.  It just doesn't seem logical.  It is obvious that all species (except the common ancestors themselves) are younger than the higher ranking taxa that include them).  Ranks are thus automatically based on RELATIVE age.  But Hennig's idea that they be based on ABSOLUTE age has been problematic from the very beginning, and it will ALWAYS be problematic no matter how robustly supported our cladograms become.

     As much as I like Peter Stevens' approach to flowering plant classification (even though I have noted "relatively" minor disagreements), I will always argue against the subjective Hennigian convention (which he still adheres to) that paraphyly must be totally eliminated.  And this is not just based on utility (usefulness), but also the basic premise that paraphyly IS a real process, and that the Hennigian convention that attempts to define paraphyly out of existence is completely unreal (and one of the most subjective misrepresentations of 20th Century biology).  How far into the 21st Century must we go before we abandon this straight-jacket of a convention, to admit that 100% holophyly was a dumb idea from the beginning, and repair the damage before it gets even worse?  Pierre may be correct that the holy grail of a single, universally acceptable classification is a myth----however, I do think we could achieve 95-99% acceptable classifications for most groups eventually, but ONLY if we abandon the holy grail of 100% holophyly in classification---which is a far, FAR greater nonsensical myth.
          ------ Sincerely,
                       Ken Kinman
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Richard Pyle wrote:
     "Objective" is a term that is perceived as being more "scientific", and is what seems to be behind the motivations of modern systematists who enshrine concepts such as "monophyly" as all-important (stability and subjective "usefulness" of nomenclature be damned), or who see techniques such as DNA barcoding as more than just an excellent tool for identification of known species (which I think it is), but also as an "objective" metric by which lines between named taxa should be drawn.
     It should be evident from the tone of my writing above (not to mention the volumes of text I have burdened this list with in the past) which philosophical camp I am in.




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