http://www.tampatrib.com/MGIODGZHFCC.html
Aug 27, 2000 - 10:09 PM
Underground, meat-eating plant found
STEVE NEWBORN
of The Tampa Tribune
Imagine a plant that grows underground, where it conducts photosynthesis
without direct sunlight.
And it eats meat.
The trick to this tiny plant is that it has a lower atmospheric pressure
than the outside, experts say. So when it ``feels'' a tiny underground
critter such as a nematode brush past, a nodule on the plant opens, sucking
it inside.
It sounds like the plot of a 1950s science fiction B movie. But it's a
living reality, stumbled upon by scientists during a field trip at Central
Florida's Archbold Biological Station.
Its ``leaves'' grow upward from the main stalk underground, while ``roots''
grow downward. The species of utricularia is unlike any other known, said
Kevin Hogan, an adjunct professor of botany at the University of Florida in
Gainesville. The discovery by Hogan and fellow botanist Stephen Mulkey
occurred while other surveys were being done, Hogan said.
Some other plants are known to have leaves underground when they are in the
seedling stage. Others grow right at the soil surface. And there are
``stone'' plants that have a shaft going through the surface, letting light
flow down into the plants.
But other than a tiny yellow flower that juts an inch above the ground in
spring - whose purpose is not known - these plants grow completely
underground.
``I don't know of any other plant that does photosynthesis underground -
certainly not flowering plants,'' Hogan said. ``Here's something that's
weird beyond belief.''
That tiny flower atop a slender stalk is what attracted the scientists'
attention. Otherwise, the plants are invisible.
Apparently, the white quartz sand of the Lake Wales Ridge lets light flow
below the surface, allowing for photosynthesis, Hogan said. The plant is one
of a number of plant types found only on the ridge, the sandy, hilly spine
of Central Florida running from Lake to Highlands counties that was the only
land in the state above water thousands of years ago.
``I've been all over the world, South America, throughout the tropics, but
this is like no place I've seen,'' Hogan said.
The only reason the plant was found is because it is on the 5,100 acres of
the Archbold Biological Station, one of the best-preserved sites on the Lake
Wales Ridge. The ridge boasts some of the most unusual - and most
endangered - species in the United States. How widespread the plant is on
the ridge is not known.
The station was founded in 1941 by Richard Archbold, who carried out
biological explorations in the Indo-Australian region, Madagascar and New
Guinea between 1929 and 1940. When World War II put an end to his
wanderings, Archbold received an estate south of Lake Placid from John A.
Roebling, a New Jersey industrialist whose family built the Brooklyn Bridge.
The center, about 80 miles southeast of Tampa, is an independent, nonprofit
research facility.
The number of species found at Archbold comprises 44 mammals, 208 birds, 25
fish, 65 amphibians and reptiles, 535 vascular plants, and more than 4,000
insects and other invertebrates.
Of these, 15 species of animals - from the Florida black bear to the Florida
gopher frog - and 28 species of plants are listed as threatened or
endangered.
During the Ice Age, the ridge was where the last remnants of temperate
forest were left. As the ice gradually drew north, the temperate forest
followed. Studies have shown the vegetation at Archbold today is very much
as it has been for 50,000 years.
The plants and animals that remained on what had been a chain of tiny
islands adapted to the dry, desertlike conditions. Many of the plants,
including scrub oaks and palmettos, have stiff, leathery leaves. Others have
hairy or tiny leaves that are curled - adaptions to reduce the loss of
water.
The recently discovered plant adapted to these conditions by growing almost
entirely underground. That protects it from evaporation, even when the
intense summer Florida sun can bake the sand up to 140 degrees, Mulkey said.
``If you're a biologist, the first thing that pops in your head is how can
these be without leaves?'' he said. ``And the flowers are self-fertilizing,
so why come above ground at all?''
Little is known about the group of plants, which is related to the
snapdragon family.
Mulkey calls them an ``evolutionary relic.'' But calling them relics might
not be the most accurate description.
Their use of variances in pressure to capture nematodes and tiny insects and
the use of photosynthesis underground point to their being highly evolved,
he said.
Steve Newborn can be reached at [log in to unmask]
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