Farewell to Species - reticulation

[B. J. Tindall]

>Thomas G. Lammers wrote:
>
>The beauty of phenetics is that is has its greatest strength precisely at
>the hierarchical levels where cladistics sometimes seems to fail us --
>infraspecific taxa and closely related species.  When the question is:
>"Here are a whole bunch of populations that are obviously very closely
>related, no doubt they are monophyletic; how many discrete entities can be
>recognized in this melange?"  -- that's when multivariate statistics are of
>the most use.  When you want to know how best to classify the orders of
>chordates, phenetics would be silly; go cladistic.  Each has value for
>answering different questions.
>

Take it a step further and one can use the same data set a) for creating a
similarity matrix and b) for looking at the individual characters. If you
knock it all down to basics the two systems are dealing with comparison by
a) measures of similarity/dissimilarity or b) analysis of individual
characters. A good example is in gene/protein sequence studies where one
may be interested in both the degree of change and the nature of the
changes. Each system has its own particular advantages/disadvantages,
depends on what the question is you are trying to answer.
Brian Tindall


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