Wandering the aisles of a supermarket several years ago, one of us (Hebert) marveled at how the store could keep track of the array of merchandise simply by examining the varying order of thick and thin lines that make up a product’s barcode. Why, he mused, couldn’t the unique ordering of the four nucleic acids in a short strand of DNA be mined in a similar way to identify the legions of species on earth?
Ever since Carl Linnaeus began systematically classifying all living things 250 years ago, biologists have looked at various features—color, shape, even behavior—to identify animals and plants. In the past few decades, researchers have begun to apply the genetic information in DNA to the task. But both classical and modern genetic methods demand great expertise and eat up huge amounts of time. Using just a small section of the DNA—something more akin to the 12-digit barcode on products—would require far less time and skill.