Scientists have observed another human-like behavior in elephants: they call each other by their names.
Researchers from Colorado State University (CSU) recorded 470 unique sounds made by elephants in Kenya, capturing different rumbles and pitches.
Using machine learning, the team discovered that the calls contained a unique tune depending on which elephant they were communicating with.
To test their theory that these sounds corresponded to different names, the team played them to the herds – and the named elephant responded by returning a sound or approaching the speaker.
The findings suggest that elephants may be capable of abstract thinking, making them much more socially complex mammals than previously thought.
According to researchers at Colorado State University, elephants communicate with each other by name
Researchers recorded 470 unique calls from elephants in Kenya that revealed their identity, age, gender and emotional state
Lead author of the study, Dr Michael Pardo, from CSU, said: ‘Dolphins and parrots call each other by ‘name’ by imitating the addressee’s distinctive call.
‘In contrast, our data suggest that elephants do not rely on imitating the receiver’s calls to address each other, which is more similar to the way human names work.’
Previous research has shown that elephants resemble humans in several ways, as the animals express compassion, grieve, use tools and raise their young for years.
And according to the latest discovery, elephants are the third creature known to call each other by name.
Researchers recorded 101 individual elephants during their fourteen-month study in the Samburu National Reserve and Amboseli National Park.
They used machine learning technology to play back the elephants’ calls to each other, confirming that they were using names to get their attention.
The technology detected the subtle differences in communication and acoustic structure to determine which elephant was being called.
Their calls conveyed a lot of information, including the caller’s identity, age, gender, emotional state, and behavioral context.
The team suspected that the animals were identifying each other, but to confirm their suspicions, they played back the recordings and confirmed that the elephants responded ‘energetically’ to the call intended for them.
“Our finding that elephants do not simply imitate the sound associated with the individual they are calling was the most intriguing,” said Kurt Fristrup, a research scientist at the Walter Scott, Jr. CSU College of Engineering.
The researchers tracked the elephants for 14 months in the Samburu National Reserve and Amboseli National Park, where they captured 101 individual elephants calling to each other.
‘The ability to use arbitrary sonic labels for other individuals suggests that other types of labels or descriptors may exist in elephant calls.’
Researchers said elephants are “expressive animals,” making it easy to read their reactions once you get to know them.
When the team played the elephants’ recordings of calls not directed at them, the animals did not respond, showing that they recognized their names, the researchers said.
“They were probably temporarily confused by the playback, but eventually dismissed it as a strange occurrence and went on with their lives,” says Pardo, who now works at Cornell University.
Elephants use trumpet sounds and low rumbling sounds to communicate, including low-frequency sounds that the human ear cannot hear
Researchers played the recordings and confirmed that the elephants responded “energetically” to calls intended for them
This isn’t so different from the way humans’ communication evolved tens of millions of years ago, the researchers said, noting that the need to develop family units and social groups likely drove the development of naming each other with abstract sounds.
Elephants use trumpeting sounds and low rumbling sounds to communicate, including low-frequency sounds that the human ear cannot hear.
“It’s probably a case where we’re experiencing similar pressures, largely due to complex social interactions,” said co-author George Wittemyer, a professor at CSU’s Warner College of Natural Resources and chairman of the Save the Elephants scientific board.
“That’s one of the exciting things about this study, it gives us some insight into possible drivers of why we developed these skills.”
Scientists say more research needs to be done to determine whether elephants name other objects they interact with every day, such as food, water and locations.