No, it can assist taxonomists, but it do not remove the need for defining and testing species boundaries. DNA-barcoding as usually done in insect is the sequencing of a small fragment of mitochondrial DNA, which is only one source of information, among others. there is also the problems with species sharing barcodes and species with large intraspecific genetic distances, that limit the usefulness of DNA-barcodes for species delimitation if not used in combination with other data. However, when such studies have been performed, it is a useful tool for identifying specimens.

Dear All,

As Svante put it, DNA-barcoding can help in difficult cases like distinguishing sibling species or identifying insect remains e.g. examination of insect or other animal gut contents.

To date, Barcoding is a very helpful tool to distinguish species in several complex with similar taxa, however, it is necessary the work of the taxonomist after the lab work.

It is a tool but cannot replace the taxonomist.

In many species complex which have been treated as a "single" and "variable" species, the DNA barcoding has provided evidences that several good species have been lumped into a different one, but always it is necessary the detailed study (taxonomist). In plants in the same history.

it is a debate... and lot of papers have been published on this question.

A research on Google Scholar with the keywords "DNA Barcoding review" give 50.300 results!

Look at for example:

Taylor, H. R., & Harris, W. E. (2012). An emergent science on the brink of irrelevance: a review of the past 8 years of DNA barcoding. Molecular Ecology Resources, 12(3), 377-388.

Moritz, C., & Cicero, C. (2004). DNA barcoding: promise and pitfalls. PLoS biology, 2(10), e354.

Personally I used this approach. I explain in the introduction to the article below the interest of this approach.

Peccoud, J., Labonne, G., & Sauvion, N. (2013). Molecular test to assign individuals within the Cacopsylla pruni complex. PloS one, 8(8), e72454.

But I am the first to argue for an integrative taxonomy approach:

Will, K. W., Mishler, B. D., & Wheeler, Q. D. (2005). The perils of DNA barcoding and the need for integrative taxonomy. Systematic biology, 54(5), 844-851.

Padial, J. M., Miralles, A., De la Riva, I., & Vences, M. (2010). The integrative future of taxonomy. Frontiers in zoology, 7(1), 16.

Yeates, D. K., Seago, A., Nelson, L., Cameron, S. L., Joseph, L. E. O., & Trueman, J. W. (2011). Integrative taxonomy, or iterative taxonomy?. Systematic Entomology, 36(2), 209-217.

If you have in front of you, say, 3 species (as you will latter find they were) in 25 specimens of Geocharis or Typhlocharis genus of carabids....use barcoding and then tell me which species........

Off course barcoding is sometimes (many times) helpfull, but be easy and relax, taxonomists will live forever!!!!!

If you want more opinions on this, there is another thread in researchgate you could dive into here: https://www.researchgate.net/post/Does_the_Future_of_Systematics_Really_Rest_on_the_Legacy_of_One_Mid-20th-Century_German_Entomologist

But keep in mind that the relative values of "barcodes" (or more in-depth phylogenetic analyses of more of the organism's genomes) vs morphology, biochemistry or other characteristics of individuals or groups of related organisms varies hugely from one type of organism to another. For one example, the lentiviruses all look alike under an electron microscope but their gene sequences are very different from one another, so DNA sequence analysis is highly useful. Domestic dogs are all very similar in DNA sequence but the various breeds look very different, so DNA analysis is less useful (although still not useless). Some organisms have left nice fossils which allow us to see a bit of their evolutionary history, but many soft organisms such as fungi and jellyfish did not leave a clear fossil record so DNA sequence analysis is more useful.

Even within a group of highly related organisms such as insects or mammals, some lineages have more interesting morphology than others (beetles vs ants for example; or deer vs wolves) so the relative value of molecular data varies too.

What defines a species is often strongly debated. There is not and cannot be a rule about species based on percent DNA similarity, although some what love such a rule. But based on that premise the species must be defined as such before a new barcode is published. If you do not know what species you are dealing with, for whatever reason, then it will be helpful to barcode the specimen and hopefully get lucky, if the species has already been barcoded. No amount of genetic research can replace a species description by a trained taxonomist. But barcoding is extremely helpful in identifying (already described and barcoded) species from pieces of tissue, from large environmental samples, from sibling species, etc.

I assume that the initial question implies if DNA-barcoding can eliminate taxonomy based on morphology.

Assumed it is cheaper and feasible (field kits) and there are thresholds for delineating species, I think its a serious alternative for a taxonomist.

With one exception coming immediately in my mind. When being incompatible , the morphology of e.g. insect genitalia can be a strong indicator for reproductive isolation (e.g. in dragon flies).

It is a (valuable) tool for a taxonomist. As is the external and genitalic morphology, a different host plant, different biotope, different flight period, different biology, response to a different pheromone composition, ...

But, for instance, to investigate if a sexual dimorph male and female are conspecific it is a very nice tool.

DNA barcoding was conceived as a molecular method to IDENTIFY (i.e. assign material to a taxon) samples, not to CLASSIFY (i.e. create taxa) them. Taxonomy is about both classifying and identifying, but classification comes first.

To develop a barcode, several individuals from a given species (say species "A") must be sequenced and these sequences must be compared to sequences from several individuals from other species (say "B" and "C"). If sequences from "A" are closer to each other than to the sequences from "B" and "C", then the barcode can be useful as a tool for identifying material (i.e. whole individuals or tissue fragments) from these species.

Thus, you need a a reliable classification delimiting species A, B and C BEFORE developing the barcode.

Hope it helps.

DNA barcoding is a taxonomic method that uses a short genetic marker in an organism's mitochondrial DNA to identify it as belonging to a particular species as a taxon. It differs from molecular phylogeny in that the main goal is not to determine patterns of relationship but to identify an unknown sample in terms of a preexisting classification [Wikipedia]. In 2003, Paul Hebert, researcher at the University of Guelph in Ontario, Canada, proposed “mtDNA barcoding” as a way to identify a species as a taxon. Barcoding uses a very short genetic sequence from a standard part of the genome the way a supermarket scanner distinguishes products using the black stripes of the Universal Product Code (UPC). An Inventory tracking method, not to confused with a phylogenetic classification!

No, for sure not, it is a great tool, but not the silver bullet. Look at chromatography, cuticular hydrocarbons, karyotyping etc. They were very hot and sexy methods, many people were hired in great positions because they used them, and now, they are a side-note, not completely useless, but surely not as hot as 20 or 30 years ago.

As an illustration, I bar-coded some 50 specimens of an Anglewing butterfly across its range. The specimens were tagged with a name Roddia l-album and R. j-album. The bar-code tree (see attached) revealed the genetic variation in this particular snippet of mtDNA across its range. It revealed that: (1) In this particular gene, the Eurasian populations are more more variable than the more uniform North American populations; and (2) both entities are genetically segregated, i.e. there are probably two species. On morphological grounds, Roddia is treated as a member of Nymphalis, which the bar-coding does not address.

However, in barcoding or a phylogenetic analysis, you will have politomies or terminal clades with only two species, which it is very usual. Is the taxonomist job to determinate if are different species or the same one.

Barcoding will play an increasingly important role in taxonomy and phylogeny in the future. New opportunities will emerge and the processes will become cheaper.

This will not displace the taxonomy and the phylogeny, but help the disciplines to new heights.

Re: Rudolf’s comment - The available DNA isolation and sequencing techniques applied to a horn of a specimen housed at the Zoological Museum in Hamburg verified the identification of this particular museum specimen as rare Sumatran rhinoceros, Dicerorhinus sumatrensis, instead as of the extremely rare R. sondaicus. See Article Museum specimens as Noah’s Arc of lost genes. The case of a ...

DNA barcoding is a tool for rapid preliminary sorting massive amount of material. Combined with other tools (let them be programmed / developed) and perhaps for some groups of organisms (e.g. for Homo sapiens) it could works. Taxonomists may be (!) required in order to finish the process of identification, but the main question is - who need these names besides ourselves (taxonomists)?!

Barcoding have been very useful for some groups (e.g., Butterflies), but for others (e.g., Plants) the results are not very good. More information need to be available and the information or resolution for many groups is basically zero or low. Why? Time, money, and preserved material are not available!! This process is relatively new and without questions, will be improved in a few years, but by now, there are many "gaps" about the information available. Taxonomist job at this point is hard to replace (in fact, some people (not taxonomist) have the "dream" to have a technic (or even a machine!) that can replace the taxonomist job in great part. The hundreds of thousands of names available to date are not 100% useful for everybody besides ourselves (according to the group), but a small percent have been useful (i.e., Prospecting, economic botany, etc). But it is the same in every basic science: many information and research is produced, but just a small percent is finally used.

• The other point of view --- to complement Dmitry's & Francisco’s answers:

Jalaluddin Rumi (13th century):

"Move beyond any attachment to names.

Every war and every conflict between human beings has happened

because of some disagreement about names.

It's such an unnecessary foolishness,

because just beyond the arguing there's a long table of companionship set and waiting for us to sit down."

Jalaluddin Rumi as interpreted by Coleman Barks.
The great Sufi mystic/poet (13th Century)

courtesy of Arthur Shapiro

DNA barcoding imposes one particular species concept. If you aren't perfectly happy with that species concept, DNA barcoding can't replace more traditional methods altogether.

DNA barcoding is accurate tool for classification. While the traditional methods of taxonomy still successful in general but there are many problematic taxa , should classify using DNA barcoding. I think in the future DNA barcoding would be the first in this aspect.

Can DNA barcoding eliminate insect taxonomy? Seemingly a straightforward question. Nonetheless, seriously misguided one and flawed in basic reasoning/logic.

1. Taxonomy is a scientific discipline dealing with recognition and naming of biological taxa (species, genera, higher taxa).

2. Barcoding is a technique/methodology devised to infer phylogenetic relationships among taxa.

The two are as separate entities as they come. It is like asking “Can artificial breathing apparatus eliminate naming of body parts”??

You decide, .... for me as a taxonomist I used DNA barcoding as verification method whether how much the two taxa before me are related. They could be the same or different and how much. In the end, I the taxonomist must decide on the status of the two.

Another use of barcoding: From an Abstract of a 2017 publication: "DNA barcoding is a technique used primarily for the documentation and identification of biological diversity based on mitochondrial DNA sequences. Butterflies have received particular attention in DNA barcoding studies, ...” Nowhere is taxonomy even implied!

you can typing with PC rather than pencil. you can confort the progress fast train.

Both of them morphological characterstics and DNA barcoding are tools to taxonomy.

I am out of this discussion, believe what you will. For sure they (the barcoding and morphological characters) are the tools. Period. So what?

Is the barcoding going to eliminate insect taxonomy? I do not think so.

Bye for now.

Can I add some little things here?- The father of DNA barcoding Dr. Hebert said "morphology and Barcoding are the hand to hand process." For the digitization of Linnaean Taxonomy--barcoding is must. So,now the era of Hebertian Taxonomy from 2003 till date. obviously Linnaean Taxonomy in our hand. You are right Joe Belicek.

DNA barcod the smart way to utilize the genomic data. Morphology the result of genome . So you can use the pencil if you want.

This is my last attempt to straighten out the persistent confusion here:

The terms TAXONOMY, SYSTEMATICS, CLASSIFICATION are not inter-chanchangeable or synonymous!

The DNA barcoding had and will have profound impact on (insect) and zoological systematics and phylogenetic classification,

but the DNA barcoding WILL NOT eliminate the scientific discipline TAXONOMY. DNA barcoding is one of the many tools this discipline uses.

I agree with your answer from the begining. dear prof. Belicek.

your idea highly satisfiable and beneficial for me and all researchers in Biology branches.

I am so grateful for your time and patience.

DNA barcoding have several advantages like it is more accurate method for species identification. furthermore, it creates a molecular database of species which is useful for evolutionary genetic studies including phylogenetics. DNA barcoding is good for the controversial species or for newly found species, but I strongly believe that combination of both classical and molecular taxonomy is the best way of study.

I recommend Brian's answer

Best Regards

Taxonomy can not be eliminated by barcoding, it is a tool meant to assist taxonomists. The two work hand in hand.

Both morphology and gene sequences would be more efficiant than one of them.