Say hello to an orca, and it might say hello back — or at least try to.
An international team of researchers, working with two orcas at an aquarium in France, have found that the whales were able to replicate the sounds of human speech, including words like "hello" and "bye-bye," as well as series of sounds like "ah ah."
The orcas could also imitate a human blowing a raspberry, or copy the sound of another orca, scientists say.
You can hear the result in a video published by The Guardian, pulling from the scientists' data.
The research — published Wednesday in the Proceedings of the Royal Society B — has implications beyond aquarium settings. It suggests that whales could be learning vocal patterns from each other in the wild.
That fits the observations of researchers in the field, who found groups of whales with "vocal dialects that are often referred to as traditions or cultures," the researchers write. "Our results lend support to the hypothesis that the vocal variants observed in natural populations of this species can be socially learned by imitation."
"We are interested in the possibility that other species also have cultural processes," the study's lead author, José Zamorano-Abramson, told The New York Times.
Luke Rendell, an orca researcher not involved in this study, noted to the Timesthat it was "somewhat ironic" that research on captive killer whales reinforces a key argument against keeping the animals in aquariums: namely, that they appear to have cultural communities in the wild. Rendell praised the work overall, noting that it involved orcas that were born in captivity, not captured.
Specifically, the researchers worked with an orca named Wikie who had already been trained to copy behaviors: A trainer would make a specific gesture, and Wikie knew she was supposed to copy whatever another orca had just done.
For this study, the trainers used that motion after noises instead of actions. They started by presenting her with sounds she already knew how to make on command, like a noisy breath or a high-pitched peeping sound.
Then they introduced "novel sounds" she had never been trained to make before. Some of them were orca sounds, which Wikie would copy either from her calf, Moana, or from a recording. She might hear a squeak like a creaky door, a wolf-whistle-esque siren, or a noise like an elephant call — sounds she had never been heard to make on her own.
Then there were the human sounds: "Ah ah," "hello," "bye-bye," "Amy," "one-two" and "one-two-three."
Those were definitely new to Wikie. But she gave it a shot. She caught on to "hello" and "one-two-three" on her first attempt, although some of the others took far longer.
To be clear, the sounds are still killer whale noises; they aren't as recognizable as, say, a parrot imitating human speech. But the researchers compared audio spectograms of the original and imitation sounds and tested the audio on human listeners who had to separate random pairings and matched pairings. They concluded Wikie had made "recognizable copies," albeit not "perfect copies."
The research involved orcas interacting with trainers, making noises in the air instead of in the water — a very different environment from what orcas in the wild would find as they hear each other vocalize and, perhaps, learn "dialects" from each other. But that's a strength, not a weakness, the scientists argue.
"We wanted to see how flexible a killer whale can be in copying sounds," co-author Josep Call told The Guardian. "We thought what would be really convincing is to present them with something that is not in their repertoire — and in this case 'hello' [is] not what a killer whale would say."
Copyright 2020 NPR. To see more, visit https://www.npr.org. 9(MDAwMTM1NDgzMDEyMzg2MDcwMzJjODJiYQ004))
