To many, urine smells like urine and vanilla smells like vanilla. But androstenone, a derivative of testosterone that is a potent ingredient in male body odor, can smell like either - depending on your genes. While many people perceive a foul odor from androstenone, usually that of stale urine or strong sweat, others find the scent sweet and pleasant. Still others cannot smell it at all.

Smithsonian researchers are among the leaders in a worldwide effort to revolutionize the way scientists identify species in the laboratory and in the field with a technique called DNA barcoding. Similar to the barcode that identifies an item at the grocery store, a DNA barcode is used to identify and distinguish biological species.