Humans call each other by name, but do other animals do this? A group of researchers say elephants seem to.

The researchers listened to recordings of a low, rumbling sound that elephants make as part of their communication with one another. The elephants in the recordings were living in Amboseli National Park and Samburu and Buffalo Springs National Reserves in Kenya. For each recording, the researchers knew which elephant was making the sound and which elephant it was addressed to. 

With the help of machine learning, the researchers worked out whether the rumbles contained distinctive sound information, the way humans often use people’s names when speaking to them. Not every recording did, but humans don’t always address one another by name either. Then scientists tried to determine how often each distinctive sound matched with the elephant that was being addressed. The machine learning showed that the sounds matched the elephants being addressed more than 27 percent of the time, much more often than when the scientists looked at random sounds. 

“There must be something in the calls that’s allowing the [technology] to figure out at least some of the time who that call was addressed to,” Mickey Pardo, a biologist at Cornell University and an author of the study, told National Public Radio (NPR). Researchers also noted that the “names” were often used by adult elephants to address young elephants.

The researchers then worked with some of the elephants they believed were being addressed in the recordings. They played some of the recordings for the elephants to see if they recognized their own “names.” The elephants didn’t seem all that enthusiastic when they heard sounds that weren’t addressed to them. Their reaction was stronger when they heard their own names.

“The elephants responded much more strongly on average to playbacks of calls that were originally addressed to them relative to playbacks of calls from the same caller that were originally addressed to someone else,” Pardo told NPR.