It was 2013 when Sanjeeta Pokharel first witnessed Asian elephants responding to death. An older female elephant in an Indian park had died of an infection. A younger female was walking in circles around the carcass. Fresh dung piles hinted that other elephants had recently visited.
“That is where we got curious,” said Dr. Pokharel, a biologist with the Smithsonian Conservation Biology Institute. She and Nachiketha Sharma, a wildlife biologist at Kyoto University in Japan, wanted to learn more. But it is rare to glimpse such a moment in person, as Asian elephants are elusive forest dwellers.
For a paper published Wednesday in the journal Royal Society Open Science, the scientists used YouTube to crowdsource videos of Asian elephants responding to death. They found reactions that included touching and standing guard as well as nudging, kicking and shaking. In a few cases, females had even used their trunks to carry calves, or baby elephants, that had died.
The work is part of a growing field called comparative thanatology — the study of how different animals react to death. African elephants have been found to repeatedly visit and touch carcasses. But for Asian elephants, Dr. Pokharel said, “There were stories about it, there was newspaper documentation, but there was no scientific documentation.”
Combing through YouTube, the researchers found 24 cases for study. Raman Sukumar of the Indian Institute of Science, a co-author, provided videos of an additional case.
The most common reactions included sniffing and touching. F or example, many elephants touched the face or ears of a carcass with their trunks. Two young elephants used their legs to shake a deceased one. In three cases, mothers repeatedly kicked their dying or dead calves.
Asian elephants communicate with touch while living, too, Dr. Pokharel said. They may sleep against one another or offer reassuring trunk touches. Younger elephants are often seen walking with their trunks wrapped together, she said.
Another frequent response to death was making noise. Elephants in the videos trumpeted, roared or rumbled. Often, elephants kept a kind of vigil over a carcass: They stayed close, occasionally sleeping nearby and sometimes trying to chase away humans who tried to investigate. Several tried to lift or pull their fallen peers.
Then there was one behavior that “was quite surprising for us,” Dr. Pokharel said: In five cases, adult females — presumably mothers — carried the bodies of calves that had died.
The observation was not totally new, though. Researchers have seen ape and monkey mothers holding deceased infants. Dolphins and whales may carry dead calves on their backs or push them up to the surface of the water, as if urging them to breathe. Phyllis Lee, an elephant researcher at the University of Stirling in Scotland, said that she has seen an African elephant mother carry her dead calf for a full day, the carcass draped across her tusks.
To human eyes, these animals can resemble bereaved parents not ready to let go of their young. While she is cautious about interpreting the animals’ actions, Dr. Pokharel said that “carrying is not a usual behavior” in elephants, as calves usually follow the herd around on their own feet.
“That carrying itself can indicate they are aware that there’s something wrong with the calf,” she said.
Understanding more about how elephants view death could “give us insight about their highly complex cognitive abilities,” Dr. Pokharel said. More urgently, she hopes that it will also help to better protect elephants that are still alive, especially Asian elephants that are in frequent conflict with humans.
“We always talk about habitat loss, we talk about all these things,” she said. “We are not talking about what animals are going through psychologically.”
Dr. Lee called the sightings referenced in the new paper “wonderful and confirmatory.”
“These rare and extremely important natural history observations suggest that an awareness of loss is present in elephants,” Dr. Lee said.
Scientists do not yet know to what degree elephants grasp the concept of death, rather than just the absence of a herd member whose trunk used to be within reach. But that does not make the animals so different from ourselves, Dr. Lee said. “Even for us humans, our primary experience is probably also loss.”