Advancing Biodiversity Science Through DNA Barcodes

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For the past 250 years, organisms have been identified through time-consuming morphological inspection, an approach that requires researchers with specialist expertise for each taxonomic group. My research program is transitioning biodiversity science from its analogue past to a digital future, a shift enabled by two methodological and technological advances. Firstly, identification systems based on the analysis of sequence variation in short, standardized gene regions (i.e. DNA barcodes) are very effective in species discrimination. Secondly, high-throughput sequencers permit the inexpensive acquisition of barcode records. Current instruments can generate 5 million reference barcodes a year for less than a dollar apiece, and they can screen bulk samples for their species composition for $0.01 a specimen. These developments are enabling biodiversity surveys at speeds and scales that were previously inconceivable. Because sequencers are doubling their output every nine months, DNA barcoding will soon make it possible to monitor and forecast biotic change on a planetary scale, but considerable work is still required to optimize protocols. Since Canada occupies 7% of our planet's land surface, it provides a good test bed. My work over the next five years has three primary goals. My students and I will extend the DNA barcode reference library for animal species found within Canada with a focus on marine and soil-dwelling invertebrates. While this work proceeds, we will also advance protocols for large-scale biodiversity surveillance. We will begin this effort in 2018 by sampling arthropods in a 150,000 km2 grid across southern Ontario. In subsequent years, this work will be extended to examine arthropod diversity in four additional ecozones. Finally, we will expand our use of barcode data to deepen understanding of factors impacting molecular evolution. Our work will make it possible to monitor shifts in species distribution and abundance in near-real time, first across our nation and then across the planet. This capability is urgently needed to address international obligations to preserve biodiversity. As a consequence, the 196 nations that are signatories to the Convention on Biological Diversity endorsed DNA barcoding in December 2015 as a key method for monitoring global trajectories in biodiversity. Our work also has important practical applications as evidenced by the broad adoption of DNA barcoding by the public and private sectors for forensic investigations, for assessing environmental impacts, for authenticating food and natural health products, and for detecting crop pests and invasive species. Aside from these societal benefits, our research will advance biodiversity science by deepening understanding of the factors which impact rates of speciation and molecular evolution.