DNA barcoding is a taxonomic method that uses a short genetic marker in an organism's DNA to identify it as belonging to a particular species.

system of species identification and discovery using a short section of DNA from a standardized region of the genome. That DNA sequence can be used to identify different species, in the same way a supermarket scanner uses the familiar black stripes of the UPC barcode to identify your purchases.

proving highly effective in identifying birds, butterflies, fish, flies and many other animal groups

The advantage of using COI is that it is short enough to be sequenced quickly and cheaply yet long enough to identify variations among species.

The COI barcode is not effective for identifying plants because it evolves too slowly, but two gene regions in the chloroplast, matK and rbcL, have been approved as the barcode regions for land plants.

Species identification using DNA barcodes starts with the specimen. Barcoding projects obtain specimens from a variety of sources. Some are collected in the field, others come from the vast collections housed in natural history museums, zoos, botanical gardens and seed banks

In the laboratory, technicians use a tiny piece of tissue from the specimen to extract its DNA

The barcode region is isolated, replicated using PCR amplification and then sequenced

Once the barcode sequence has been obtained, it is placed in the Barcode of Life Data Systems (BOLD) database - a reference library of DNA barcodes that can be used to assign identities to unknown specimens.