One huge advantage of drones is that these little robots can go places where people can’t, including areas that might be too dangerous, such as unstable structures after a natural disaster or a region with unexploded devices. Researchers are interested in developing devices that can navigate these situations by sniffing out chemicals in the air to locate disaster survivors, gas leaks, explosives and more. But most sensors created by people are not sensitive or fast enough to be able to find and process specific smells while flying through the patchy odor plumes these sources create. Now a team led by...