As the saying goes, you catch more flies with honey than vinegar, but (discounting that vinegar is actually a great way to trap fruit flies), there’s an even better method: smell like rotting meat. As a subset of flowering plants figured out long ago, many flies and some beetles are drawn to the putrid and foul over the pretty and floral. Exploited correctly, these insects‘ instincts can make them great pollinators.
But how does a flower conjure up the odor of decaying flesh? For a long time, scientists haven’t been quite sure. One persistent theory was that plants produce these compounds passively, through oxidation of more common precursor chemicals, or that these plants partner with bacteria to produce their stenches. Yet new research indicates that, actually, many plants have everything they need to actively stink it up solo. Flowers across at least three stinky families share a similarly evolved genetic pathway to carrion mimicry, according to a study published May 8 in the journal Science.
With a few small modifications, a single gene that’s present in most plants and animals can turn flowers into stink factories. The altered gene works by generating a specific enzyme. That enzyme subsequently transforms a common protein byproduct into dimethyl disulfide (DMDS), a strong-smelling chemical that’s created when bacteria break down rotting flesh.
Depending on the context, DMDS’s odor also suggests notes of fermented, pickled radish, dried meat, or human feces, says Yudai Okuyama, lead study author and an evolutionary biologist who studies plants at the National Museum of Nature and Science in Tokyo. “It’s a very bad smell,” he notes. But Okuyama and his colleagues managed to follow that stink to a beautiful set of discoveries.
The scientists began their research by surveying plants in the genus Asarum, c
