It seems my barcoding rant from last week has caught the eye of Alex Smith of the University of Guelph. Alex is the force behind numerous DNA barcoding projects, including the pioneering study on Malagasy trap-jaw ants, and I have elevated his reply from the comments:
Hi Alex – happened by myrmecos this morning, saw your essay and the comments that have piled up over the past several days and couldn’t help add my two cents.
1) A barcode is a epistemological tool, an ‘evaluation criteria’ for identification and can act as a catalyst for discovery. It is not an ontological truth that defines a species. Anyone who has proposed barcoding as a concept is clearly incorrect – but has anyone? “We test the epistemological hypothesis that the barcode MOTU can be used as a surrogate for the identification of diversity within and between collection localities.” (Smith et al 2005). To paraphrase Fitzhugh (2008) barcodes can be used as an “epistemological bases for indicating phylogenetic hypotheses”.
2) Identifying the species and ignoring the biology? Much of what the people that I work with have tried to do have been far more integrative than such a statement suggests (Fisher and Smith 2008, Smith et al 2008, 2007, 2006). Again – I know of no one that would support the idea to ‘ignore biology’.
3) Many of the pros for integrating DNA into existing taxonomy, ecology, and evolutionary biology programs are accentuated if one of the genes is a standardised marker that permits comparison between localities, researchers and taxa. This is a clear plus to inclusion of a standardized gene – and but clearly stops short of being an argument for stopping all questions after this first pass evalulation.
4) ‘the barcoders’ – This is a straw man. There is no mob of phylogenetically illiterate cabal of taxonomy-hating gel jockeys. I hope that the moment in time when ‘us, them’ language can be used to characterise, or be made caricatures of, is passing. This is a tool – I know of no contractors who call themselves ‘#2 Robertson’s” because that is their standard first pass screw when constructing a home. There is no them.
Will a standardized single gene identifier solve all problems in biology? Un-equivically no. Could it make future hypotheses regarding species membership and terminology more transparent and reproducible – yes. Many people’s distaste for the metaphor is abundantly clear, but I’ve got to tell you that what I’ve experienced for the past five years is that when talking to many people on the planet (the non-biologists, the teachers, the government bureaucrat,, the administrators, the… generally majority of humanity) – the edges of the metaphor where it is biologically meaningless become less relevant. What is more immediately relevant is that ‘they ‘understand an IUPAC identifier; this code gives me information about something (most often the price). Is co-opting this societal understanding to add to some degree of biological literacy “marketeering” or is it communicating science?