Sniff, sniff. When it comes to naming particular colours, most people do so with ease. But for odours, it’s much harder to find the precise words. However, the Jahai people, a group of hunter-gatherers living in the Malay Peninsula are exceptions to this rule. An earlier study found that for the Jahai, odours are as simple to name as colours. A new study published in Current Biology on January 18 suggests that the Jahai’s special way with smell is related to their hunting and gathering lifestyle.
According to Asifa Majid of Radboud University in the Netherlands,
“There has been a long-standing consensus that ‘smell is the mute sense, the one without words,’ and decades of research with English-speaking participants seemed to confirm this. But, the Jahai of the Malay Peninsula are much better at naming odours than their English-speaking peers. This, of course, raises the question of where this difference originates.”
In order to ascertain whether it was the Jahai who have an unusually keen ability with odours or whether English speakers are simply lacking, Majid and Nicole Kruspe at Lund University in Sweden looked to two related, but previously unstudied, groups of people in the tropical rainforest of the Malay Peninsula, the hunter-gatherer Semaq Beri and the non-hunter-gatherer Semelai.
Semelai people are an Orang Asli people of the Proto-Malay people group found in Negeri Sembilan and Pahang states of Malaysia. They are traditionally horticulturalists, combining shifting rice cultivation with the collection of forest products for trade.
Not only do the Semelai and Semaq Bari people live in similar environments, they also speak closely related languages. The researchers set out to find how adept they were at naming odours.
“If ease of olfactory naming is related to cultural practices, then we would expect the Semaq Beri to behave like the Jahai and name odours as easily as they do colors, whereas the Semelai should pattern differently,” the researchers wrote.
That’s exactly what they found.
Kruspe and Majid tested the colour- and odour-naming abilities of 20 Semaq Beri and 21 Semelai people. Sixteen odours were used: orange, leather, cinnamon, peppermint, banana, lemon, licourice, turpentine, garlic, coffee, apple, clove, pineapple, rose, anise, and fish!
For the colour task, participants were shown 80 Munsell colour chips, sampling 20 equally spaced hues at four degrees of brightness. Kruspe tested participants in their native language by simply asking, “What smell is this?” or “What colour is this?”
Results clearly indicated that the hunter-gatherer Semaq Beri performed on those tests just like the hunter-gatherer Jahai, naming odours and colours with equal ease. However, the non-hunter-gatherer Semelai people performed like English speakers. For them, odours were quite difficult to name.
These results indicate that the downgrading in importance of smells relative to other sensory inputs is a recent consequence of cultural adaption, the researchers say.
“Hunter-gatherers’ olfaction is superior, while settled peoples’ olfactory cognition is diminished,” Majid says.
According to the researchers, these findings challenge the notion that differences in neuroarchitecture alone underlie differences in olfaction, suggesting instead that cultural variation may play a more prominent role.
Other questions are also raised by this study:
“Do hunter-gatherers in other parts of the world also show the same boost to olfactory naming?” Majid asks. “Are other aspects of olfactory cognition also superior in hunter-gatherers,” for example, the ability to differentiate one odour from another? “Finally, how do these cultural differences interact with the biological infrastructure for smell?”
She says it will be important to learn whether these groups of people show underlying genetic differences related to the sense of smell.
This study was published in Cell Press. You can read it here.