Scientist Explains Why Dogs Can Smell Better Than Robots

Dogs can smell explosives like landmines, and detect medical conditions including seizures, diabetes, and many forms of cancer -- with up to 98% accuracy. Inventor Andreas Mershon wants to replicate that -- and put a nose in every cell phone. WIRED's Emily Dreyfuss spoke with Mershon to find out why that's easier said than done, and to learn what building a robotic nose has taught us about smell.