Tuesday, October 23, 2012

A new fighting fish

DNA Barcoding has often been criticized for not following through on new discoveries. There are a lot of studies that resulted in the discovery of potential cryptic species but many of these new entities have never been named and formally described. Many of them bear an interim taxonomic name or a number code which gets propagated quickly. One of the reasons for that might be that it takes an awful lot of time to go through the lengths of formal description by following the rules set by International Commission on Zoological Nomenclature

Frankly, for researchers in earlier stages of their career - and I consider myself one - it is also an intimidating thought to publish a description that is initially (and sometimes exclusively) based on molecular evidence knowing that there are some big names in your taxonomic field, full of resentment towards DNA Barcoding, eagerly waiting for a Barcoder showing a weak spot. I had the arguable pleasure of receiving some snarky comments in the past years and I haven't even started to formally describe some fish although I probably should.

Furthermore, a taxonomic description doesn't give you much credit which in turn could count for your career. Unfortunately, they way we measure success in science and assess candidates for academic positions relies heavily on impact factors and citation indices. This is an alarming development in general and a huge problem for taxonomy in particular. 

What are we supposed to do as researchers that don't have a tenured faculty position? We are to a considerable extend measured based on our publications and their impact. It might sound harsh but it is true - a description of a new species or a revision of a genus doesn't help you to position an article in a high ranked journal, and that's what many search committees are looking for to find the best candidates in a big pile of applications.

So, I am not surprised that so many potential species discovered by DNA Barcoding haven't got a name yet, and I haven't even talked about the fact that the rate of discovery is simply becoming to high for traditional taxonomic culture to catch up. That's why it is important to showcase examples where things are falling into place although it might take a few years before it happens.

Betta mahachaiensis (from article)
The fighting fish genus Betta is a good example for a group where we haven't be able to worm out all secrets yet. In 2010 a DNA Barcoding study contributed new (molecular) evidence to the case for a new species and furthermore indicated two more overlooked species in the genus Betta. Two years later the confirmed species was formally described as Betta mahachaiensis and further descriptions were announced therein. These beautiful little fish belong to a group of Betta that build bubble nests, floating masses of bubbles blown with an oral secretion or saliva that will eventually host their eggs. Males will build those nests of various sizes and thicknesses, depending on the male's territory and personality. Some males build constantly, some occasionally, some when introduced to a female and some do not even begin until after spawning. Fishes of this new species have been found with their nests in the phytotelma of a palm. The molecular findings are one part of the entire story. There are also morphological traits characteristic for the new species.

Nipa palms with B. mahachaiensis in their phytotelma
The message for those critiques that say DNA Barcoding research leaves behind a lot of unfinished business is that we do what we can to follow currently accepted practice. However, as I tried to made clear in my introduction to this post there are quite a few factors making this extremely difficult, especially for young academics, and it requires the entire community to resolve the real issues behind that. Offending comments and destructive reviews bashing DNA Barcoding are not helpful at all and hopefully a relict of the past.

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