Barcodes of Life

What DNA can reveal

• Laura Tangley
• May 01, 2007

WHEN IT COMES to identifying species, looks can be deceiving: In a prelude to an ambitious plan to genetically "barcode" all life on Earth, an international scientific team has identified nearly two dozen previously unknown bird and bat species based on DNA sequences of a gene that is shared by all higher organisms. All of the proposed new species look similar or identical to existing ones.

For the bird study, researchers examined the DNA of 643 North American species and discovered 15 that are genetically distinct from currently accepted species. In Guyana, they analyzed 87 kinds of bats and identified 6 new species.

"People have watched birds for so long we might think every different tweet has been heard, every different color form observed," notes biologist Paul Hebert of the Biodiversity Institute of Ontario at Guelph University. "But there are many cases of deep genetic divergences within what are currently called single species."

To date, the "Barcode of Life" database has catalogued more than 25,000 species of all types. Hebert and other project scientists, who published their latest results in Molecular Ecology Notes, predict that DNA analysis will ultimately reveal at least 1,000 "hidden" bird and mammal species.