The image was taken by a camera trap set to record the movements and behavior of African elephants. Credit: Connie AllenIntagliata: Allen and her colleagues investigated that idea by testing African elephants’ ability to tune in on a very specific smell: urine. You see, elephants pee a lot—some 12 to 15 gallons a day—and that urine can contain an array of chemical cues. Allen: We’d wait for elephants to urinate and, within 20 minutes, go and collect these fresh urine samples. Intagliata: Then they set up camera traps on seven elephant trails.