African elephants use a range of combined gestures and vocalisations in different social scenarios, according to collaborative research by a group of animal behaviourists from the Universities of Vienna, St Andrews and Portsmouth.
The study, published this month in Communications Biology, shows that elephants greet each other using visual, acoustic, and tactile gestures depending on whether the other elephant is looking at them. The study also finds that elephants use different combinations of gestures and vocalisations to greet each other, possibly to help recognize and bond with each other when they meet.
"I have been studying elephant vocalisations for over 20 years", explains Dr Angela Stöger, senior author and zoologist in the Department of Behavioral and Cognitive Biology at the University of Vienna. "What remained unknown was whether elephants greet each other by combining gestures and vocalisations in specific ways, which might help shed light on the functions of their greetings".
Lead author Vesta Eleuteri is also based in the University of Vienna's Department of Behavioral and Cognitive Biology. She added, "Most research exploring animal communication focuses either on vocalisations or on gestures. But many animals, including humans, get their messages across by combining vocalisations and gestures."
"Previous studies had reported elephants engaging in elaborate greeting rituals, where they use vocalisations and various physical actions. However, it was still unclear whether these physical actions were non-deliberate movements or actually gestures intentionally produced for communication."
Researchers studied the signals used during elephant greetings by observing nine semi-captive African savannah elephants living in the Jafuta Reserve, Zimbabwe, between November and December 2021.
They found that the sensory modalities of the actions used by elephants varied depending on whether their partner was looking at them, suggesting that the elephants were selecting the appropriate signal to greet their partner with.
"Elephants were more likely to use visual gestures (such as ear-spreading, trunk-reaching, or trunk-swinging) when their partner was watching", said Vesta Eleuteri, "but used acoustic gestures (such as ear-flapping) or touched their partner when not being watched. This suggests they are able to take into account the other elephant's visual attention when gesturing."
The researchers also found that elephants greeted each other with specific combinations of rumble, trumpet, and roar vocalisations with gestures such as ear-flapping, ear-spreading, and tail-touching or with other seemingly less deliberate physical movements such as tail-raising and waggling.
Previous research has observed chimpanzees and other apes altering their gesture modalities according to whether they are being watched and combining vocalisations and gestures, so the authors propose that these communication methods among elephants may have evolved independently to mediate social interactions in these distantly related species which share complex societies and advanced intelligence.
"Many of our methods for studying gesture come from work with great apes", said Dr Catherine Hobaiter, from the School of Psychology and Neuroscience at the University of St Andrews, "So it's been a fun challenge to adapt these to elephants, who not only have all sorts of new and interesting body parts to gesture with, but also use such a wide range of modalities - including smell!"
Together, the findings show that elephants greet by deliberately altering their gestural communication methods depending on whether they have the visual attention of the individual they are greeting, and by combining vocalisations and gestures.
Category Research
