Elephant trunks are long-distance food detectors

An elephant’s trunk is the Swiss army knife of appendages: It’s used to breathe, communicate, and even lift objects. Now, a new study finds another use—sniffing out food across long distances.

Researchers have long known that elephants and other plant-eating mammals seek their supper with their eyes. But scientists at the Adventures with Elephants facility near Bela Bela, South Africa, wanted to know whether they could do the same thing with their trunks. So they collected 11 plants eaten by wild African elephants (Loxodonta africana), six of which the animals loved and five of which were not nearly as appealing.

In one experiment, the elephants had to use their sense of smell to choose between two small samples of plants concealed in black plastic bins. The elephants tended to pick “preferred” plants when the other option was a nonpreferred species, but they had a harder time choosing if both plants were either “preferred” or “nonpreferred.” In a second experiment, the elephants were put into a Y-shaped maze, with a different plant at each end of two 7-meter-long arms. In this formulation, they always chose the preferred plant over the less desired species, the researchers report in Animal Behavior . They were even able to differentiate between plants that fell closely together on the love-hate scale.

The results suggest that African elephants can detect plant aromas from a distance, the researchers write, using their trunks to navigate the landscape and find the best places to dig up dinner.