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Michael McLeod
A FUN STORY I WROTE YEARS AGO. A LITTLE LONG.
THE MYSTERY OF THE FIRST FLOWER
 
By Michael Mcleod and Orlando Sentinel Staff | Orlando Sentinel
UPDATED: October 25, 2018 at 6:11 PM EDT
David Dilcher is a paleobotanist. He studies plants. Dead plants. How exciting can that be?
Exactly.
Spotlights await a dinosaur scientist who settles a secret of tooth and claw. Paleobotanists labor in the shade. But plants have their mysteries, too, hidden among the ancient leaves. Thirty years ago, Dilcher set out to solve one of them:
How did flowers come to be?
He has traveled all over the world in pursuit of that question, visiting dozens of fossil sites, squinting at the remains of tens of thousands of prehistoric plants.
Now he thinks he has found an answer.
He keeps it in a small box in a drawer in his desk.
And not everyone agrees about what’s inside.
From the street, the old Florida Museum of Natural History in Gainesville looks more like a subway entrance than a place of higher learning. It hunkers halfway into the earth, a squat, raw concrete structure covered on one side by an overgrown embankment. Its exhibits are gone, moved across the University of Florida campus to a sleeker building. The only things inside the abandoned old bunker these days are the offices and labs of natural history professors such as Dilcher, who taught biology at Indiana University for 24 years before coming to UF 12 years ago.
At 65, he could easily be mistaken for just another frumpy, preoccupied academic. Both collar buttons of his button-down dress shirt are undone. In place of a tie, a magnifying glass dangles from a lanyard around his neck. He’s not wearing a wristwatch because it stopped two months ago and he hasn’t gotten around to having it fixed. His hair is a frayed, gray semicircle.
But his headquarters has the feel of a kid’s clubhouse.
A locker in his lab is filled with tiny chunks of petrified wood. They look like Lincoln Logs that have been chopped up by gnomes and stacked into firewood for some ancient dollhouse hearth. He carries a variety of weird-looking, golf-ball-size seeds around in his pocket and passes them out like party favors. And he may be the only member of the National Academy of Sciences who bought swampland in Florida. He and his students prowl the 65-acre preserve, taking core samples of the soil, studying environmental changes over thousands of years.
His office is a science-fair jumble filled with renderings of strange-looking plants, exotic, long-dead specimens that could pass for transplants from some distant galaxy. In a drawer at the far end of the narrow enclave is the small wooden box. It looks like it should have a row or two of expensive cheroots inside.
Instead, couched in red velvet, lies a piece of off-white limestone with a fossilized imprint at its center — a yellowish, broken, two-inch twig. Against the red velvet, it has the faded elegance of a withered blossom that someone pressed between the pages of a dusty volume long ago.
Dilcher spins halfway around in his chair and makes a guilty little shrug. Then he wheels back and carefully replaces the box. Part of him thinks the fossil is too precious to be tucked away like this; it should be on display in a museum somewhere. “I really shouldn’t have this,” he says. “But it’s just a small part of what we found.”
What they found is a 125 million-year-old fossil, originally unearthed by a Chinese peasant about 250 miles northeast of Beijing, where ancient limestone outcroppings checker a 50 square-mile rural area. The Yixian (yee-SHUN) Formation, as it is called, has become a hotbed for paleontologists, who have coaxed a spectacular series of exquisitely preserved feathered dinosaurs, ancient mammals and primitive birds from its layers of rock and volcanic ash.
Dilcher thinks his two-inch twig is just as important as any of those finds.
When this plant was alive, small, early mammals foraged nearby and volcanoes simmered in the near distance. Growing in the waters of a shallow lake, with its topmost branches waving a foot or so above the surface, it did not look like anything you would order from FTD or see on a Rose Bowl float. It was, not to put too fine a point on it, a weed.
Nothing on the plant looked like a flower, judging from two fossils that have been studied by Dilcher and his collaborator, Chinese geologist and paleobotanist Sun Ge. There were no pretty, symmetrically arranged petals. Things had not gotten to that point yet. But Dilcher believes they had begun.
On the tips of the stems, stretching several inches above the surface of the water, are wrap-around leaves that resemble pea pods. Dilcher thinks they are carpels — shieldlike structures that protect the seeds inside. He’s equally convinced that the wispy growths on the stem beneath them are stamens.
Carpels and stamens are the plant world’s equivalent of the opposable thumb. They are the building blocks of one of the most important inventions in natural history: flowers.
It is hard to imagine life without them. But 150 million years ago, the world was filled, almost exclusively, with pine trees and ferns. You could find a plant in any color you wanted, as long as it was green. When flowering plants appeared, it was like the scene in a famous old movie when everything switches from black and white to color and Kansas gives way to Oz.
Without flowers, the planet would not be the flamboyant, fragrant, fruitful, Crayola sort of place it has become, not that we would notice, since we probably wouldn’t be here, either.
Human beings use flowers to celebrate and decorate, to sympathize and apologize, to woo their lovers and to soothe themselves. When anthropologists discovered that Neanderthals buried their dead with flowers, they took it as evidence that early humans had begun to care about each other.
But flowering plants nurture the body as well as the soul, making it possible for mammals to flourish. From apples to zucchinis, all the fruits and vegetables and grains that feed us, either directly or indirectly, are produced by flowering plants.
WORKING HIS WAY BACK
A poet once described flowers as “the hieroglyphics of angels.” Scientists have labored for decades to break the code, ever since the days of Charles Darwin, who called the origins of flowering plants “an abominable mystery.”
Modern science has two ways to solve that mystery.
Field researchers such as Dilcher start in the past and work forward, seeking out fossils of extinct plants and comparing them to living plants.
The newer approach is to begin in the present and work backward, examining the DNA of modern flowering plants to determine which are most directly descended from the creations spawned in the primeval greenhouse.
Ideally, the two approaches — the fossil hunters and the genetic analysts — would point in the same direction.
Until Dilcher and his Chinese fossil turned up, they did.
Genetic analysts who study modern plant DNA have deduced that the earliest flowering plants grew on land. Many of them champion a small, bushy plant called Amborella, which grows only on the South Pacific island of New Caledonia, as a kind of living fossil — the sole survivor of the original line of flowering plants.
If Dilcher is right, the Amborella fans are wrong. The fossil contradicts the test tube, even though many scientists were sure about the test tube results — or as Yale paleobotanist Leo Hickey puts it: “Nonetheless, the skull sits there on the table, looking at us.”
Dilcher’s find has widened a rift between the new wave geneticists and the old guard fossil hunters. On one side are genetic researchers such as paleobotanist Michael Donaghue, of Yale University, who say they’re not ready to accept Dilcher’s argument that the first flowers may have evolved in the water.
“What you wish is that you could have the thing and grow it and see what’s going on,” says Donaghue.
Other paleobotanists are so impressed with Dilcher’s remarkably well-preserved fossil find that they blame the doubts of their colleagues on stubbornness and sour grapes.
“People think scientists are lofty individuals who are above such things, but we aren’t,” says William Crepet, chairman of the L.H. Bailey Hortorium at Cornell University.
Dilcher says he just wants his colleagues to take a look at the evidence and work together to help him find a place in the family tree for his Chinese plant, called Archaefructus, which means “ancient fruit.”
“Cooperation is always best,” he says.
It’s a lesson, he says, that he learned from flowers.
SCIENCE WITH A DASH OF ART
After spending the better part of his 65 years as a professor, Dilcher has that lecture-hall, PBS groove in his voice, slow enough that you can take good notes, scholarly enough that you figure you had better.
Yet sometimes he sounds more like a poet than a scientist. “Flowers became the best advertisers in the world,” he muses, his voice hushed and dreamy. “Flowers have developed a wonderful way of saying, ‘Come find me. I’m beautiful. Look what I have for you.’ “
Dilcher has spent most of his life answering that ad. He has sought out ancient flowers all over the world — Norway, Australia, Germany, Brazil, Afghanistan, India, Thailand, Turkey, Greece, Spain, Argentina, Chile, Colombia, Alaska. He’s found the remnants of prehistoric flowers in the Saudi Arabian desert, and he’s found them on Elsmere Island in the high Canadian arctic, where the frozen remains of what was once a warm, lush landscape awaited him.
He has found flowers preserved in clay, in sandstone, in shale, petrified peat, and coal. He has amassed a collection of 350,000 fossils, written 170 scientific papers about them and earned himself that membership in the National Academy of Sciences, a coveted, blue-chip, invitation-only society reserved for scientists at the top of their fields.
But Dilcher has humble roots. He grew up as the son of a factory worker in Anoka, Minn., the hometown of Prairie Home Companion storyteller Garrison Keillor. It was a small town: When Dilcher received a student loan, it was from Keillor’s uncle; when he commuted to the University of Minnesota, he rode with Keillor’s sister.
Dilcher worked his way through college as a caretaker on the 11 p.m. to 7 a.m. shift at a mental hospital, grabbing a couple hours of sleep then going to classes during the day.
He graduated, but the night job made it a struggle, and the experience left Dilcher with a longstanding sympathy for students who are financially strapped. In later life, he has helped put a number of needy med school and biology students through college in China, Afghanistan and the United States.
He dates the beginnings of his own career as a scientist back to a cold winter day during his sophomore year of college. Still unsure of what to choose as a major, he was walking down Hennepin Avenue, the road that ran through the middle of the Minneapolis-St. Paul campus.
Freeze frame: While other students hurry by, eager to get out of the frigid air and into classrooms, Dilcher is staring at something you can find plenty of during the long Minnesota winters: ice. Though it is well below freezing, has been for days, the ice on the side of the road is slowly disappearing. He realizes the ice has begun to sublimate (the term for what happens when a solid turns directly into a gas).
Big deal, most people would say. To Dilcher it’s a moment of subzero enlightenment. He realizes that he spends his days looking for cave crickets, tending to plants in his room, driving his parents crazy by keeping a hive of bees in the yard. So he decides to major in botany. He starts taking science classes and gets a part-time job sawing up petrified plants for one of his professors, which attracts him to paleobotany as his own specialty. He goes on to earn a doctorate from Yale and decides that he wants to take on something significant as his life’s work — “Something I could do that would add something useful, something that had to do with the origins of life.”
THE THRILL OF THE CHASE
Thirty years ago, the notion of studying ancient blossoms was considered impractical. Blossoms, the thinking went, were just too delicate for enough of them to have survived as fossils to study.
Dilcher disagreed. He cultivated relationships with other scientists who had discovered fossilized flowers. He also found quite a few specimens on his own, beginning his search in 45-million-year-old clay pits in Kentucky and western Tennessee before moving on to other locations in the United States and across the world.
He worked out his own methodology for studying the blossoms and proved the critics wrong long before Archaefructus came along.
“He is, above all, persistent,” says Kevin Nixon, a paleobotanist at Cornell University who has collaborated with Dilcher in studying Archaefructus.
Dilcher is so persistent that he says he does not plan to retire any time soon. It should be interesting, he says, as other fossils of early flowering plants are discovered and he and other paleobotanists continue to haggle over which came first.
“I don’t want the search to be over,” he says. “I like the search too much to give it up.”
For the moment he’s happy just to make a visit to his collection in the basement of the old museum.
He wanders down an aisle of filing cabinets, pulls out a shallow drawer and lifts a yellowing sheet of newspaper. Beneath it is a scattering of fossils, laid out in the shallow drawer like cookies on sheets, each about the size of a thumb print. At first glance, they look like seashells. But they are petals, dating back 100 million years, to an extinct plant that grew in Nebraska when flowers were still a novelty in the natural scheme of things.
Once, they were something like morning glories. Now, they are beyond withered. They have turned into stone. No color. No fragrance. No beauty, save to the man who has been their loyal suitor all these years.
“Oh, I can see them,” says Dilcher. “In my mind’s eye, I have no problem at all seeing what this flower must have looked like. To me, this is a bouquet.”
He sounds like somebody who should be off in another department, reading Elizabethan sonnets. Standing there, enraptured by blossoms that have long since died, he seems more like a hopeless romantic than a scientist.
His colleagues would disagree. So would his wife, Kathy.
He is a wonderful man, she says. A good father to their two children, a son and a daughter, both grown. A soft touch for students who need help. A loyal companion to her.
But does he ever send her flowers?
She sighs.
“Hardly ever,” she says.
Originally Published: July 14, 2002 at 12:00 AM EDT
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