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Before the next time you take a sip of wine, you might want to make a toast to wasps. Those big scary insects play a key role in making wine, we're told. NPR's Elizabeth Shogren reports new research reveals their special function and suggests that preserving biodiversity might be more important than you think.
ELIZABETH SHOGREN, BYLINE: Years ago, Italian microbiologist Duccio Cavalieri was doing field research in the vineyards of the Chianti region, and he noticed something special about the relationship between grapes and wasps, particularly a type of wasp called the European hornet.
DUCCIO CAVALIERI: If you are looking at the berry and who was eating the berry, who could actually eat the berry were these big hornets.
SHOGREN: Other insects couldn't pierce grape skin. Cavalieri had an inkling that he was observing an important secret about wine. It took nearly 15 years and some sophisticated DNA sequencing to prove his hunch.
CAVALIERI: Wasps are indeed one of wine lovers' best friends.
SHOGREN: It turns out wasps have yeast in their bellies and they regurgitate it into the grapes they bite. Yeast is the stuff that turns grape juice into wine. The type of yeast a winemaker uses will affect the way it tastes. So the yeast in the wasps gut gets passed into the wine and imbues it with the flavor of the region.
CAVALIERI: Since the times of the Romans we have realized that it was important to improve some qualities and characteristics of the wine to have flowers and insects around the vineyard. And now we really know more about it.
SHOGREN: Cavalieri comes from a family of winemakers in the Chianti region, so he's delighted to be able to unveil one of the mysteries of wine. He published his team's results in the proceedings of the National Academy of Sciences. He says what's really important to him about his discovery is that it hints at just how interconnected the natural world is.
CAVALIERI: I think everything is linked.
SHOGREN: Those links aren't always apparent to us. Winemakers never knew that wasps were kicking off the fermentation process for them.
CAVALIERI: Yet, if we lose this, we lose complexity. And one of the most beautiful things of wine is the fact that basically it's complex, it's made of several parts and it communicates to several parts of your brain.
SHOGREN: Harvard evolutionary biologist Anne Pringle wasn't involved in the research, but she says it sends a warning to wine growers who might be inclined to use pesticides to get rid of wasps and hornets.
ANNE PRINGLE: If you'd like to have your grapes fermented by local yeasts, which I think many vineyards do, then you have to have these insects around.
SHOGREN: Pringle says there's a larger message.
PRINGLE: Personally, what this tells me is how little we know about how the world works and we're running out of time.
SHOGREN: The natural world is changing quickly because of stresses like climate change, invasive species, habitat loss and pollution. And Pringle says many species already have been lost or may soon vanish before we learn what magic they perform for Earth's ecology.
Elizabeth Shogren, NPR News.