[Taxacom] Dark taxa: GenBank in a post-taxonomic world

[Richard Zander]

Well, since traits do not evolve, taxa do, then they are linked. You need to know what the taxa are on which phylogenetic traits are based. If you don't then juggling changes in traits results in a clustering by similarity. Parsimony gives one a natural key since the traits are nested, but it is still a cluster analysis, not an evolutionary analysis. The implication that similarity implies evolution is trivial unless it is followed by investigation of what taxon gave rise to what other taxon.

"Distance matrices, clades, traits tracked over phylogenies" are meaningless unless connected with diachronic (through time) evolution, meaning "change of species by descent" in Darwin's own words.

R.

On 4/12/2011 6:54 PM, Richard Zander wrote:
> Interesting idea that taxonomic names may be unnecessary for certain 
> research using just sequences.

That kind of research is done all the time when you want to know how traits developed across clades. Whatever the name is, it is irrelevant as long as you have a distance matrix.

> IMO taxonomic names represent scientific theories of groups in nature.

Sure.

> Without such theories of groups in nature, exactly what can sequences 
> offer as data for research?

Distance matrices, clades, traits tracked over phylogenies, etc.

> Is it research involving a scientific theory?

Yup, testing whether a trait evolved randomly, or whether traits have been under directional selection in some clades and not the other.

> I think Markov chain reasoning is probably okay for some things, but 
> what things given no scientific names?

Names are irrelevant for many studies.

(puts devil's horns down)

Kim

 
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Richard H. Zander 
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