Imma Perfetto
Cosmos science journalist
For the first time, wild male African elephants have been documented using ‘let’s go’ rumbles to signal to their group that it’s time to move on.
Until now, this behaviour was thought to be exclusive to dominant female elephants to keep tight-knit family groups together during coordinated departures.
The vocalisations, detailed in a study in the journal Peer J, are initiated by the most socially integrated, and often most dominant, males in close-knit social groups.
“We were astonished to find that male elephants, typically considered to have loose social ties, engage in such sophisticated vocal coordination to trigger action,” says lead author Caitlin O’Connell-Rodwell, a research associate at the Centre for Conservation Biology at Stanford University in the US.
“These calls show us that there’s much more going on within their vocal communication than has previously been known.”
O’Connell-Rodwell, who first recorded the behaviour in 2004 while conducting fieldwork at the Mushara waterhole in Etosha National Park, Namibia, says it was “thrilling to realise that these males were using complex vocal coordination like the females were”.
The team collected audio and visual recordings from 2005 to 2017, then analysed the vocalisations’ acoustic properties and patterns and used social network analysis to understand relationships and hierarchy among the males.
They found that both female and male elephants can initiate a ‘let’s go’ call. This starts with an initiator’s rumble, which is followed by the next (often highly bonded) individual. Each elephant in the group waits for the preceding call to nearly finish before starting their own.
O’Connell-Rodwell says this creates a harmonious, turn-taking pattern akin to a barbershop quartet.
“It’s very synchronised and ritualised. When one goes high, the other goes low, and they have this vocal space where they’re coordinating,” she says.
Last month Cosmos reported on another study that found wild elephants use personal ‘names’ to address each other. The findings indicate that elephants use nouns to communicate.
“In our paper, we show that elephants are using verbs in the form of this ‘let’s go’ rumble,” O’Connell-Rodwell says.
“If they are using noun-verb combinations together, that is syntax. That is language.”
