Taxonomy, the science of classifying living things according to shared features, has always been a part of human society. Identifying organisms has grown in importance as we monitor the biological effects of global climate change and attempt to preserve species diversity in the face of accelerating habitat destruction. Less than two million of the estimated 5-50 million plant and animal species have been identified. Classical taxonomy falls short in this race to catalog biological diversity before it disappears.
Now, DNA barcodes allow non-experts to objectively identify species – even from small, damaged, or industrially processed material. Just as the unique pattern of bars in a universal product code (UPC) identifies each consumer product, a "DNA barcode" is a unique pattern of DNA sequence that identifies each living thing. Short DNA barcodes, about 700 nucleotides in length, can be quickly processed from thousands of specimens and unambiguously analyzed by computer programs.