If describing a smell leaves you struggling to find the right words, it might be down to how you put food on the table.
Researchers studying two communities living in tropical rainforests have found that while a hunter-gatherer group could easily describe different odours, their plant-growing neighbours floundered — suggesting different ways of finding food could be behind humans’ proficiency, or lack of it, when it comes to putting a name to a scent.
Smell has long been regarded as the most meagre of our senses, losing importance over evolution as humans’ sense of vision developed. But recent studies have suggested the faculty is nothing to be sniffy about, with humans’ capacity to distinguish different odours mooted to be on a par with that of dogs.
But while English-speakers struggle when it comes to describing smells — a finding some believe reflects smell’s role as the sensory poor relation — researchers say recent work with the Jahai hunter-gatherer community shows not all humans struggle.
“In our previous work we had found that this idea that we are really bad at describing smells — which has come from Plato and you still see on the internet today — isn’t universal,” said Asifa Majid, professor of language, communication and cultural cognition at Radboud University. “The Jahai, who live in the Malay Peninsula, were as good at describing smells as they were colours, and they were much better than English speakers — we wanted to know what was going on, exactly.”
With the Jahai and English-speakers living in very different environments and speaking unrelated languages, Majid and co-author Nicole Kruspe, from Lund University in Sweden, turned to two groups in the Malay Peninsula who speak a closely-related language: the Semaq Beri hunter-gatherer community and the Semelai horticultural community that grows rice and other plants.
The researchers gave 20 Semaq Beri participants and 21 Semelai participants 16 marker pens containing odours ranging from peppermint to fish, and asked them to sniff each and describe the smell. In addition, each participant was shown 80 different colours of varying hues and brightness, and asked to describe them.
The researchers then compared the answers within each group and quantified the level of agreement on the labels used: the higher the agreement, the better able the group was judged to be able to identify a colour or smell.
The results, published in the journal Current Biology, reveal that the Semelai — like English-speakers — are better at naming colours than smells. However, the Semaq Beri participants were just as able to name a whiff as a colour.
What’s more, the team found that while both languages contain particular descriptors for smells, the Semelai preferred to use words that described the source of the pong — as English-speakers do with phrases like “banana-scented” .
“Perhaps as people go from a hunter-gatherer lifestyle to other, more settled modes of subsistence, they stop using this vocabulary — so there is something about the hunting-gathering lifestyle that seems to particularly call for it,” said Majid, adding that she believes the idea that smell is not important for humans, or that smell and language are not connected well in the brain, has been squashed.
“These studies show that in fact humans do care about smells, that it is something that they can communicate about, but that it is something that is not maybe maintained in other modes of life,” she said.
The study, however, has limitations, including that the team did not test whether all participants had equal powers of smell perception or differentiation, probe what about the hunter-gatherers’ lifestyle might be behind their prowess in naming odours, or unpick whether genetics might play a role.
Anna Franklin, a professor of visual perception and cognition at the University of Sussex who was not involved in the study, said the research clearly showed that how people talk about their perceptual experience of the world is shaped by how they live. But, she added, there was plenty still to probe.
“A pressing question for further research is whether these cultural differences in how we talk about odours are associated with cultural differences in sensitivity to odours,” she said.