Locality data

Tim@ tim@gingerwoodnursery.com
Wed, 31 Oct 2012 17:53:23 PDT
Great discussion.  From my perspective molecular taxonomy is a useful tool in understanding relationships between species and genera.  Alone it has its faults as does any attempt to strictly define a concept that really can't be pinned down.  No technology will end the lumpers vs splitters conflict.  In the end its still based on human interpretation.   All of the molecular works I've seen ( mostly looking at Zingiberaceae ) are geared toward defining genera and how those genera are related to each other.  For focused studies on one genus, useful information can be obtained and it has helped settle some debates that taxonomists have had.  When using morphology alone, there is often the issue of what features are important in defining a species.  When two similar looking plants are regarded as one species by some and distinct by others this difference in the interpretation of the morphology will remain deadlocked without another aid.  This is where molecular research was defin
 itely helped, proving that the two species questioned aren't even that closely related.  Now, going back to the morphology, there is a very noticeable difference in flower structure that some recognized as worthwhile and others chose to ignore as insignificant.  This feature can now be used as an identifier.    

I've not seen a useful key to the species of (insert genera of choice) that is a list of DNA codes.  We use morphology.   I think the two disciplines can be used together quite well.  The main issue I see is the rather poor sampling of individuals of one species.  Often only one to a few individuals of the same species are used.  When there are several individuals it still is rarely a deliberate sampling to cover the range of the species, instead it is just what was available. In certain species (again referring to gingers) the amount of variation in the wild is amazing and certainly underrepresented in the sampling that is sequenced and compared. 

Undersampling is the cause of so much confusion in taxonomy starting from the beginning.  It is still an issue and will remain for ...ever.  We want to say THIS is what a species is, instead of THESE are what a species is.  When talking about such great diversity I think clear cut answers are often impossible to find, and that's really not such a bad thing.  There's nothing wrong with a few 'sp. aff.'s' in your collection ;)

Tim Chapman

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