Our atomic noses.

Normally, when we think of the way we smell things, we think of the molecules of a smelly substance – like a rose or a garlic roll – wafting into the air and then landing on our olfactory nerve like flies stuck to flypaper. The way they stick determines how they affect our sense of smell. But, as Nature reveals, what’s actually going on might be a little more about “vibration” and “energy” than we thought:

The flies can also be conditioned by electric-shock treatment to exhibit a selective aversion to either form of the molecule, showing that they can clearly distinguish between them. The authors report their findings in the Proceedings of the National Academy of Sciences.

Skoulakis and his colleagues say that the results offer strong support to a controversial theory of how olfaction works; a theory proposed previously by one of the report’s co-authors, Luca Turin at the Massachusetts Institute of Technology in Cambridge. According to Turin, odorants are identified not according to their molecular shape, but their atomic vibrations.