One condition did strip the elephants of their ability to detect the aroma of abundance: swapping out the perforated lids for solid ones that scents couldn’t pass through. This, Plotnik says, hints strongly at the incriminating culprit being smell alone.

“I’m really glad to see a study like this done,” says Caitlin O’Connell, a biologist and elephant expert at Stanford University who was not involved in the study. “I know how difficult these studies are, but these experiments are really nicely set up. They leave little left to be questioned about whether what they see [is real].”

Because the elephants in the study weren’t free-living, it’s not yet clear how these behaviors translate to wild populations, or how they’d benefit elephants in social or ecological contexts, says Marcela Benítez, a behavioral biologist at Georgia State University who was not involved in the study. But smell can have a lot of advantages over vision. “When you have visual stimuli, it’s only as good as what’s in front of you,” she says. “It doesn’t travel well. But something like scent can remain...it has a temporal element you don’t get with vision.”

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Elephants are highly social. Their trunks help them communicate through sound, smell, and touch. Image Credit: Kyslynskyy, iStock

And given how smell-oriented elephants are in navigating their surroundings, it’s likely they’re putting these appendages to good use in daily life, O’Connell says. Quantitative trunks could come in handy for locating rich caches of food, or keeping track of a herd. They could also help elephants identify potential mates or avoid conflicts with competitors. “It’s critical for elephants to understand their world through smell,” she says. “For them to be able to distinguish quantity makes a whole lot of sense.”

What exactly “more” or “less” smells like at the cellular level, and how this information gets processed in the brain, still aren’t clear. (Though, based on the study’s results, it’s probably unlikely that elephants can sniff a container and tell the exact number of seeds inside.) Answering these questions will require more research—and, given our own limitations in the odor department, a hefty dose of creativity. “[Understanding how to smell quantity] might be like describing colors to someone who’s never seen before,” Miller says.

Understanding this sensory skill, however, could help preserve a species in decline. Fewer than 40,000 Asian elephants remain in the wild—and “we’re running out of time to save them,” Plotnik says. “They’re remarkably intelligent animals we still know very little about.”

But conservation will be difficult without clearer insights into how these animals see—and smell—the world around them. “If you want to really understand how smart an animal is, you have to put yourself in their shoes,” Plotnik says. “What this study tells us is, if you want to do that with an elephant, you’re going to need a trunk.”

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