The Great Pretender

Spoofing an exotic flower of the Andes to solve an evolutionary puzzle

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FAKING OUT FLIES WITH A 3-D PRINTER: Can you find the real orchid? Only one of the images on this page is of an actual Dracula lafleurii—the others are silicone shams, created with the help of a 3-D printer to study the importance of the flower’s maroon markings in attracting mushroom flies. The real orchid is above. The colors for the three imposters were digitally matched to the original but even so, the flies weren’t interested in the solid (right) and striped (below) varieties; only the spotted version (lower right) rivaled the real deal in terms of fly-attracting appeal. That suggested that the pattern of the markings is more important than color, in terms of drawing pollinators that ensure the flower’s survival.

The Dracula orchid is so-named because its blood-red coloration and long, petal-like sepals suggested to some the famous vampire. But the flower is more con artist than menace.

Native to Central and South America, the orchid survives because it uses trickery to entice mushroom flies into landing on it, triggering pollination. But what draws the hungry flies?

Is it the flower’s labellum, a central petal that visitors take for an appetizing mushroom but which is, alas, an imposter? Or the orchid’s elaborate markings? Perhaps it’s the cocktail of intoxicating fungal scents emanating from different parts of the flower?

orchid.red.royScientists were at a loss. But they knew that answering this question would help unlock how flowers ensure their orchid.stripe.roysurvival through mimicry.

To solve this evolutionary riddle, UO biologists Tobias Policha and Bitty Roy called upon the latest technology—a 3-D printer.

Working with visual artist Melinda Barnadas of California, the scientists created lifelike flowers of silicone, testing each of the orchid’s features individually in an Ecuadorean forest. The answer: Sight and smell count equally—the flies find irresistible the orchid’sorchid.spot.roy mushroom-like fragrance, and the spotted sepals advertise that it’s a good place to stop for a bite.

The fabrication method used by the UO team is expected to open new doors across evolutionary ecology.

“It’s a really important contribution,” said Florian Schiestl, a botanist with the University of Zurich in Switzerland. “It’s going to be an important technique for pollination ecology in general.” —Matt Cooper

Photo credits: Tobias Policha (top); Bitty Roy (three model orchids); Aleah Davis (below)

The biologists created “chimeras”—part real, part fabricated—to test the importance of look and scent in drawing pollinators. Pictured above, left to right, are a real Dracula orchid; an artificial one (with more white, above the first); a third (center) with an artificial labellum—the mushroom-shaped petal in the center—and real sepals; and a fourth (right) with a real labellum and fake sepals. The scientists found that the spotted sepals and the fungi-like labellum—and their scent—all drive attraction.

HYBRID BEAUTIES: The biologists created “chimeras”—part real, part fabricated—to test the importance of look and scent in drawing pollinators. Pictured above, left to right, are a real Dracula orchid; an artificial one (with more white, above the first); a third (center) with an artificial labellum—the mushroom-shaped petal in the center—and real sepals; and a fourth (right) with a real labellum and fake sepals. The scientists found that the spotted sepals and the fungi-like labellum—and their scent—all drive attraction.