Dark, hidden treasure and a very good dog

 

Rye patiently awaits his reward—a toss of the ball in Heather Dawson’s hand—for finding a truffle.  C. WILCOX/SCIENCE Christie Wilcox, Editor, ScienceAdviser When I came across Heather and Hilary Dawson’s paper on studying truffles with the help of a dog , I was immediately intrigued. While I’d heard about truffle dogs (and truffle pigs, of course), I had never heard of the animals’ fungi-finding talents being used for mycological research. When I learned that I could tag along on a truffle hunt and meet the pup—a deep red golden retriever named Rye—the story became irresistible. So I packed my camera, audio equipment, and an overnight bag into my Subaru Forester, and drove several hours south to the Washington-Oregon border to hang out with Heather and a merry band of Oregonian mycologists—and see Rye in action. He certainly didn’t disappoint, but only a fraction of my experience made it into the Science magazine piece I wrote. Rye found so much it was simply impossible to put it all in the story, even with a related podcast. Early on in our trek through an oak forest, Rye sniffed out a truffle that was buried a solid 20 centimeters deep—a variety that would almost never be found using traditional raking methods. Unfortunately, as he dug down to it, he accidentally shattered it. Still, from a tiny fragment, Heather knew it was a black Elaphomyces—and probably an undescribed species. Ones she had found on previous excursions appeared distinct from known species, but she needs more samples to do the morphological and genetic analyses. “This is a group that I plan to work on. I just have to get enough collections,” she told me. “Good boy,” she told Rye, tossing the ball. “Go find another.” As we walked through the oaks, we passed lots of little holes in the soil about the same depth as the one Rye had made, places where small animals had dug up fungi. “Lots of critters finding the truffles before us,” she said as we trudged on. A few hours and countless holes later, she began to sound frustrated: “They must have reached their fill at some point, right?” As we continued to search, Heather told me that the idea of truffle dogs sniffing out biodiversity isn’t new. Hidden in the records of European truffles are notes about species that were discovered by truffle dogs. “They’ve been doing this in Europe for hundreds of years, where truffle dogs really have a very distinct footprint and culture because of the super valuable culinary truffles,” she says. But now, people are starting to grow truffles in other places, and recognize the tasty fungi growing natively all over the world—and train dogs to find them. Truffle dogs have only really been used in the Pacific Northwest for a few decades, Heather noted. The more of them there are, the more opportunities there will be for dogs like Rye to contribute to research. In their paper published in Ecology and Evolution in November, Heather and Hilary noted that many of the Genea Rye found don’t morphologically match known species, and they told me a number of genetic sequences they’ve gotten so far are distinct from published ones. Heather said it’s likely Rye has uncovered dozens of undescribed truffle species—he may have found some in the few hours I spent with him. I watched him unearth more Genea, which given the dearth of species descriptions from the Pacific Northwest, are probably undescribed. And there was a Gautieria, the known species of which aren’t usually associated with oaks—this truffle became the lead photo for my magazine story about Rye. There are other very good dogs that I didn’t get the opportunity to meet, like Monza—the furbaby of Tennessee truffle dog trainer Lois Martin who uncovered two new North American species of Tuber. Monza is trained to sniff out Tuber melanosporum , the black or Périgord truffle—one of the most expensive fungi in the world. Though native to Europe, there are efforts to cultivate it all over the world to increase the bounty, including in the Eastern U.S. Still, Martin was surprised when Monza began indicating that she smelled a truffle in some trees near a baseball field at a local park. Martin sent that fungus to University of Florida mycologists Matt Smith and Benjamin Lemmond, who determined it was a related but previously undescribed species. They dubbed it T. canirevelatum —Latin for “revealed by dog”—“to honor all the dogs that are finding truffles,” Lemmond told me. There’s just so little known about truffles because, of the major kinds of life, fungi are far less researched than plants, animals, and even bacteria. “Fungi used to be really uncool,” Smith told me. While that’s changed in the last five to ten years, mycologists still have a lot of catching up to do. Fungi are so poorly studied that “there are still some mushroom groups that you can go out in your backyard and find a mushroom, and it’s a new species,” Smith said. And when it comes to their ecology, “we know basically nothing … That is amplified for the fungi that fruit below ground, because so few of us have a truffle dog named Rye that can find everything.” This Elaphomyces truffle with gray spores that Rye found is likely an undescribed species.  C. WILCOX/SCIENCE As we headed back to the cars, Rye started to dig once more. Heather was careful not to let him get too far on his own before gently moving the soil away herself. And after several minutes, there it was: a nice, marble-sized black Elaphomyces. When she cut it open, the spores inside were pale gray—a feature that sets it apart, as most other species have dark black spores. “The first time I saw this, I was like, ‘Oh no! This is immature.’ Now I’ve found enough that I’m almost positive these are mature spores,” she said. When she describes the species, she told me, she thinks she’ll name it after the spores’ ashy color. “You were a very good boy,” she told Rye as she threw the ball a second time after the find. He brought it to me, and I tossed it a third. “You’re getting spoiled,” I told him. But the truth is, he spoiled us. In addition to all his contributions to science, Rye has found Heather plenty of tasty truffles. Though we didn’t find any culinary species (Oregon blacks or whites) on our trek, she sent me home with a few of the dozens of garlicky-smelling Tuber candidum he unearthed—“I think it might have some culinary potential,” she said—and told me to “experiment.” I shaved some over a bowl of plain pearl couscous when I got home, and I have to say, I think she’s onto something. To Heather, the truffles aren’t Rye’s real gift. “For me, it’s a treasure hunt in the woods with my best friend,” she says. “I think there’s nothing I would rather be doing with my time. The fact I’m finding so many cool things is just a cherry on top.” LISTEN TO THE RELATED SCIENCE PODCAST