Classroom Resources: Democratizing Taxonomy

By Marguerite Holloway
April-June 2006 (Vol. 7, No. 2)

Read the article >>

Discussion Questions

1. There are several different applications of DNA barcoding. In “Democratizing Taxonomy,” biologists Dan Janzen and Winnie Hallwachs describe the use of DNA barcoding as a tool to promote “bioliteracy” in the general public and elevate concern for the biodiversity crisis. Barcoding is also promoted as a technique for scientists to assign unidentified individuals to species, enhance the discovery of new species and identify cryptic species or species clusters. Barcoding can additionally serve as a diagnostic tool, helpful in the identification of marketed or traded species of conservation concern. Which of these complementary applications is likely to receive more conservation funding? Do these uses require different tools to be developed?
2. The democratization of species identity may be hampered without the parallel democratization of species knowledge. Do you think the broad scale utility of DNA barcoding can be fully achieved without published species descriptions being released from copyright or publisher restrictions? Some people estimate that it will take tens of thousands of years to describe the world’s species using current taxonomic methods. Does being able to tell things apart using barcoding solve this problem? We need to understand biodiversity in its ecological and community context. Will barcoding help or hinder or be neutral to this effort?
3. What are some applications of DNA barcoding for endangered species management, particularly with regard to processed food products and sustainable fisheries management? How might DNA barcoding enhance the precision and efficiency of field studies, particularly those involving diverse, immature life stages or difficult to-identify taxa or in countries with stringent export permit regulations?
4. Barcoding requires the development of a comprehensive sequence database associated with voucher specimens of species described and revised by trained taxonomists. However some critics are concerned that an emphasis on barcoding will compete with taxonomy through an increased institutional focus on securing funding and space for large high-throughput labs. Do you feel that an increased focus on barcoding has the potential to exacerbate the decline of classical taxonomy? Could it deepen a disconnection of scientists with the ecology of their study organisms as some critics put forth? Could barcoding actually increase the need for taxonomists and strengthen our understanding of community ecology instead? How could the historical collections in natural history museums play a part in DNA barcoding?
5. DNA barcoding currently is focused on sequencing of the cytochrome c oxidase I (abbreviated COI) gene, a short, easily sequenced mitochondrial DNA sequence. What are the advantages and disadvantages of this approach? Would the resolution of ambiguous species boundaries (due to recent speciation, male-biased gene flow, ancestral polymorphism, hybridization etc) improve if more genes were sequenced? Could there be a trade-off between inclusion of more genes per species and slower progress towards field utility?
6. Requisite steps or infrastructure required before barcoding can serve as an inexpensive, publicly available tool include: 1. Large-scale deposition of sequence data into GenBank, 2. Development of inexpensive handheld units, 3. Access to low cost information technology, 4. Continued or increased support from taxonomists, conservation biologists and ecologists to link morphological, ecological, functional and status information with sequence data, 5. Improved public database infrastructure to support this information and 6. Immense public education and outreach for the dissemination of such tools. Do you feel these are reasonable goals in both developed and developing countries? Much of the world’s poorest live in marginal areas, where biodiversity is most fragile and the impact of biodiversity loss most extreme. Is DNA barcoding a useful conservation technique in these areas?
7. Do you think an increased understanding of the number of species on earth whether obtained through extrapolation or mass barcoding efforts has the potential to spur behavior changes in humans? If we supplement this cataloging with detailed ecological understanding of each species, would people be more motivated?

Websites for Further Information

• Guelph Centre for DNA Barcoding: www.barcodeoflife.org
• Consortium for the Barcode of Life (CBOL): www.barcodinglife.org/views/login.php
• The Barcode of Life Blog: phe.rockefeller.edu/barcode/blog
• GenBankñThe National Institute of Health’s public collection of DNA sequences: www.ncbi.nlm.nih.gov/
• The DNA Barcode Data Analysis Initiative (DBDAI): dimacs.rutgers.edu/Workshops/DNAInitiative/
• The Barcode of Life Data Systems (BOLD): www.boldsystems.org/views/login.php

DNA Barcoding in the News

• “Science Intends to Tag All Life,” BBC: news.bbc.co.uk/2/hi/science/nature/4251309.stm
• “DNA Barcoding Spots New Species,” New Scientist: www.newscientist.com/article/mg18424672.600.html

DNA Barcoding Initiatives

• Lepidoptera: The All LEPS BOL initiative is assembling barcodes for 25,000 species of Lepidoptera from Australia, Canada, Costa Rica, and the United States: www.lepbarcoding.org/
• Fishes: The FISH-BOL campaign is gathering barcodes for at least 15,000 fish species with an emphasis on marine species: www.fishbol.org/
• Birds: The All-Birds Barcode Initiative (ABBI) is assembling DNA barcodes for all 10,000 bird species within 5 years: barcoding.si.edu/AllBirds.htm
• Invasive and Pest Species: The International Network for Barcoding Invasive and Pest Species (INBIPS). Aims to serve as a clearinghouse, forum and catalyst for the creation of barcoding projects on invasive and pest species: barcoding.si.edu/INBIPS.htm
• Endangered Vertebrates: barcoding.si.edu/VertebrateConservation.htm

Key Concepts

• Species identification
• DNA barcode
• Taxonomy
• Biodiversity conservation

Selected Literature

• Gregory, T.R., 2005. DNA barcoding does not compete with taxonomy. Nature 434, 1067-1067.
• Janzen, D.H., Hajibabaei, M., Burns, J.M., Hallwachs, W., Remigio, E., Hebert, P.D.N., 2005. Wedding biodiversity inventory of a large and complex Lepidoptera fauna with DNA barcoding. Philosophical Transactions of the Royal Society B-Biological Sciences 360, 1835-1845.
• Lorenz, J.G., Jackson, W.E., Beck, J.C., Hanner, R., 2005. The problems and promise of DNA barcodes for species diagnosis of primate biomaterials. Philosophical Transactions of the Royal Society B-Biological Sciences 360, 1869-1877.
• Moritz, C., Cicero, C., 2004. DNA barcoding: Promise and pitfalls. Plos Biology 2, 1529-1531.
• Schindel, D.E., Miller, S.E., 2005. DNA barcoding a useful tool for taxonomists. Nature 435, 17-17.
• Spash, C.L., Hanley, N., 1995. Preferences, information and biodiversity preservation. Ecological Economics 12, 191-208.