Probing biodiversity and evolutionary processes through DNA barcoding

点击翻译按钮获取中文摘要

Over the past 250 years, more than 1.7 million species of eukaryotes have been described. Despite this substantial effort, the task of species recognition remains complex. Many species (perhaps 90%) remain undescribed and formal descriptions do not ensure subsequent recognition because the morphological nuances that separate closely allied species ordinarily require a specialist for interpretation. The barcode of life initiative aims to revolutionize both the discovery and identification of life by exploiting sequence diversity in a standardized gene region as a basis for sequence recognition. Although this approach remains controversial in some circles, the Consortium for the Barcode of Life now includes more than 120 member organizations in 40 nations. The rapid growth of interest in DNA barcoding reflects both the scientific promise of this approach and the need for a newly sophisticated capacity for species recognition to curb invasives, to better manage agricultural and forestry pests and to advance biological research at large. Most prior DNA barcoding studies have been modest in taxonomic and geographic scope. However, because of my lab's deep involvements in DNA barcoding, we are able to execute substantive projects. Over the next 5 years, I will direct my NSERC Discovery research to the assembly of a comprehensive DNA barcode library for 35,000 species of Lepidoptera (butterflies and moths) that occur in North America and Australia. The progress of this work will be aided by collaborations with taxonomists and ecologists on each continent. By coupling an 'industrial-scale' collection capability with our capacity for barcode analysis, we will make rapid progress. Our work will demonstrate the feasibility of developing barcode libraries for even the most diverse insect groups. The resultant barcode library will be an important enabling tool for much biological research; it will certainly also aid taxonomic work by speeding species discovery. Finally, our work will reveal much about species ages and origins. The contrast between patterns of diversity in Australia and North America, two continents with divergent histories of climate and biogeography, promises intriguing new insights into speciation.