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DCIM\100GOPROElephants use their trunks to both touch and smell novel objects, including cameras, present in their environment

Elephants use their trunks to both touch and smell novel objects, including cameras, present in their environment.

PHOTOGRAPH BY THINK ELEPHANTS INTERNATIONAL, Inc.

Karl Gruber

for National Geographic

Published December 28, 2013

Say it ain't so, Dumbo. Elephants rely on their trunks and not those big ol' ears to find their way to food and likely to solve other puzzles, report scientists. (See: "Elephants at Risk.")

Elephants are renowned for their acute senses of hearing and smell, both of which play central roles in their everyday life. But until now, it was not known how important these senses were for basic, everyday tasks. (See: "Elephant Photo Gallery.")

"This is one of the first times, to our knowledge, that elephants were shown to use olfaction [smell] in a basic intelligence test," said Joshua Plotnik, an animal behavior scientist from the University of Cambridge, U.K., who led the study, recently published in the journal Animal Behavior.

The results of the study offer insights into how elephants think and could be used to figure out ways they might be dissuaded from raiding farmers' food, suggest the study authors. The authors also suggest that scientists may underestimate the smarts of pachyderms (and other animals) by relying too much on intelligence tests tied to sights or sounds, instead of smells.

Food IQ Test

In the study, seven Asian elephants first had to choose between two buckets that were potential sources of food (one bucket had food and one didn't), a standard "location test" of animal smarts in monkeys, birds, dogs, and other creatures.

The elephants were cued with a sound, the shaking of a closed bucket to reveal whether it contained sunflower seeds. In this first test, the elephants' odds of picking the full bucket were no better than chance.

In the second part of the study, however, the elephants were allowed to smell one of two buckets, either an empty one or one that smelled of food. The elephants had to choose between the bucket they had smelled and a new, mystery bucket. Elephants that were first exposed to an empty bucket always rejected this bucket and selected the "mystery" bucket instead.

This suggests that elephants are using smell as part of their decision-making process. They remember that the first bucket did not smell of food and choose the other option.

Smell Surprise

The results are surprising, say the researchers, because elephants are gifted when it comes to acoustic communication, so it is not hard to imagine that, if needed, they could use sound to find food. (See video: "Elephants Communicate While at Play.")

"Although elephants probably do not use sound to find food [in the wild], we did think that the elephants would be able to find the food in a task where only auditory cues were provided," says Plotnik.

The findings have important implications on many levels. For instance, it advances our understanding of how these animals interact with their environment.

"Our research suggests that their sense of smell may play a more important role in their decision-making process than it does for other species, and that this may have important implications for the design of future studies of their intelligence," says Plotnik.

It also could provide valuable tips for avoiding human-elephant conflicts. Plotnik explains, "If we know how elephants find crops to raid, perhaps we can find ways—using olfactory deterrents, for instance—to stop them before they raid."

The study results could be used to help scientists design more accurate animal-behavior experiments, on elephants and other species, said experts not involved with the study.

"For too long, we have tested all sorts of animals on stimuli that we, humans, find most salient," explains primatologist Frans de Waal of Emory University in Atlanta. "We thus stack the deck against animals that differ from ourselves, and sometimes conclude from negative results that they are dumber than us."

This means that future studies of animal behavior ought to focus more on discovering each animal's special abilities before anything else.

"[This study] shows just how primate-centric some of our cognitive tests really are," adds Yale evolutionary psychologist Laurie Santos. "If we really want to understand elephant cognition, we need to start thinking outside the visual-auditory box."

19 comments
Helen Smith
Helen Smith

if you judge a goldfish by its ability to climb a tree it will always appear stupid


Christian Mathurin
Christian Mathurin

Come on guys, we've been watching your programs and could clearly see these things in their normal behavior and instincts naturally! These tests just under-minded the intelligence of the elephants. Did they explain to the elephants what they were supposed to do in these tests, (LOL) so as not to leave the elephants wondering what am I doing here and what's with these white buckets? Perhaps this was meant for the kid's channel because I keep hearing "Duhhh" to these findings. It still doesn't explain why it was an actual study and not a blatant observation! Just sayin' but still love ya guys! Find better/smarter scientists, please! ;)

Evelyn Pantel
Evelyn Pantel

Is anyone surprised that they use their trunks to smell and locate food?  Did anyone think they used their ears? 

robbie butler
robbie butler

donkeys and elephant and pigs plus tapirs and other horse animals were related some way 1000000 years ago because of their similar habits of eating and drinking plus getting dirty they have to be they should look into this

Barbara Cullom
Barbara Cullom

I believe I learned from National Geographic that elephants' ears help the creature stay cool.    But I also believe that the ability to smell water (among other things) is an important part of elephant life.

Jim Levenick
Jim Levenick

Isn't this making rather too much of the fact that an elephant can smell food (as opposed to no food in the empty bucket)?  


Not much of an "intelligence test", if you ask me...

Otto Fad
Otto Fad

Thanks to NatGeo for sharing and keep up the great work, Dr. Plotnik!

Daria Maria Koukoleva
Daria Maria Koukoleva

I think scientists think in an overcomplicated way - is it not obvious that elephants must surely use their sense of smell to survive in their habitats? A smart survivor would say to use all the senses you have: I'm sure elephants would've picked that up too in their existence..

keerthi kumar
keerthi kumar

Yes , it is elephants easily grasp the food by smell,it is my personnel observation at Bandipur National park it is in Karnataka,The Mahoot  brings  the regular food in ball form, the elephant will grasp the food by by smell and its anxiety to eat.

Perry Lourdes
Perry Lourdes

I'm curious to know if during the experiment the elephants went solely based on smell or if they touched their trunks to their Jacobson's organ after smelling. 

Perry Lourdes
Perry Lourdes

I'm curious to know if during the experiment the elephants went solely based on smell or if they touched their trunks to their Jacobson's organ after smelling.

Josh Plotnik
Josh Plotnik

Michael Rozza, thanks for your comment. Actually, we did ask the mahouts, as we work very closely with them. As we state in the paper, the mahouts helped inform the study from the beginning. They believed vision and audition would be the most important cues, and in fact, it was neither vision nor audition. This shows that no matter how long you've interacted with elephants, you have to think / see / hear / smell like them to really understand how they're thinking!

Michael Rozza
Michael Rozza

Humans and elephants have interacted for thousands of years and scientists are only now figuring this out? (Of course, the kid who waters the elephants in the circus, or the mahout in India probably knows all this, but nobody asked them!)

Craig Busse
Craig Busse

Let's not forget that elephants also use their trunks remarkably well for manipulation -- a substitute for hands.


This story triggered a very old memory for me when as a boy visiting the Ringling Brothers, Barnum and Bailey Circus I got to got feed peanuts to the elephants. I don't know if such things are still allowed but I could hold out a peanut and an elephant would "inhale" it from my hand into a nostril and then relay it to its mouth. I was fascinated. From that day forward, I always knew that elephants are wonderful creatures.

Xaali O'Reilly
Xaali O'Reilly

@Daria Maria Koukoleva Organisms don't get to "pick stuff up" during their existence to adapt in the way they like. "Smart survivors" don't get to choose their senses and too may animals is has been advantageous to loose some of their senses (e.g. blind cave fish).

But that is besides the point. The study wasn't testing whether elephants use their sense of smell or not; even if they were, in science you need evidence for every point, no matter how trivial it may appear. You yourself said "MUST" and "SURELY" rather than stating that they do.

They also didn't claim it was a complicated study or a breakthrough discovery, although why NG have covered it as news is perhaps less clear.

Stannous Flouride
Stannous Flouride

@Daria Maria Koukoleva I think you misunderstand the study. 

Of course the elephants use their sense of smell to survive, as do all other animals except us.

The question is: Do elephants use their sense of smell as part of their decision making process?

And do they use this more than their visual or auditory clues?

The answer to both seems to be yes.

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