Last week, we discussed how the science of smells is being used by law enforcement officials, who rely on the latest dog training techniques and technology to sniff out criminal activity. Now a new study shows that the animals with the fastest sense of smell known to humans—the masters of quickdraw in the great olfactory shoot-out—are none other than rats. The intrepid rodents can differentiate between odors in just 140 milliseconds—no doubt a trait that has long come in handy for finding open garbage cans. Prior research has shown that rats take as little as 50 milliseconds to determine the direction of a smell, while humans need a whopping 700 milliseconds to process one sniff.
Rats have been trained and put to work by police departments on tasks such as sniffing out landmines in Colombia (a job that can be too dangerous for dogs, whose greater mass can more easily trigger explosions). And researchers are looking for even more ways to put these lightning fast noses to good (for us, anyway) use—though somehow it’s hard to envision a team of leashed rats waiting for you at the customs gate.