This is truly Earth’s dawn forest
and I find the large woody vines most interesting. I presume that they were rooted, and then the
question becomes how so rooted and how did it interact with the mounds of
decaying vegetation. The ecology is
believed to be much less efficient at reducing those mounds of branches. This forest may well help elucidate that
issue.
The rooting may well have been
vine like and have occurred along the trunk at various locations which was in
contact with soil. This is certainly a
good strategy for exploiting a densely overburdened soil base that is covered
with living vines and massive amounts of detritus. As the detritus reduces the growing vine
could expect to eventually make contact with sufficient rooting conditions.
The other trees are palm like and
that is also an early adaptation allowing the plant to gain elevation. All good stuff.
Giant Vines & Towering Trees: Ancient Forest
Unearthed
Stephanie Pappas, LiveScience Senior Writer
Date: 29 February 2012 Time: 01:00 PM ET
An artist's rendering of the 380 million-year-old forest at Gilboa , New York
CREDIT: Frank Mannolini
One of the earliest forests in the world was home to towering palmlike
trees and woody plants that crept along the ground like vines, a new fossil
find reveals.
The forest, which stood in what is now Gilboa , N.Y. ,
was first unearthed in a quarry in the 1920s. But now, a new construction
project has revealed for the first time the forest floor as it stood 380
million years ago in the Devonian period.
"For the first time, we actually have a map of about 1,200 square
meters (12,900 square feet) of a
Devonian forest," said study researcher Chris Berry, a scientist at Cardiff University
in the United Kingdom .
"We know which plants were growing where in this forest, and how they were
interacting."
Fossil forest
At the Riverside Quarry in Gilboa ,
New York , a construction project
unearthed a preserved forest floor 380 million years old.
CREDIT: William Stein
The fossilized
forest floor contained three types of enormous plants. The first,
known as the Gilboa tree or Eospermatopteris, was once thought to be the
only type of tree in the forest; quarry workers have been carting specimens out
of the area since the fossil plants were first discovered. This tree was tall and
looked like today's palm trees, with a crown of branches at the very top.
But an even stranger specimen lurked in this ancient forest. Amid the
towering Gilboa trees were woody creeping plants with branches about 6 inches
(15 centimeters) in diameter. These giant plants, known as progymnosperms,
seemed to lean against the Gilboa trees for support, perhaps even climbing into
them occasionally, Berry
said.
"Those trees were covered in little branches which sprung out
in all directions and made a sort of thicket on the floor of the forest," Berry said. "That
was a big surprise."
The researchers also found a fragment of a third type of tree,
lycopsids, which would later dominate the Carboniferous period from about 360
million to about 300 million years ago. They reported their findings Wednesday
(Feb. 29) in the journal Nature.
Understanding an ecosystem
The new view of the ancient forest is changing paleontologists'
understanding of what the
landscape looked like. The earliest researchers thought the forest was
in a swamp, but Berry and his colleagues,
including study leader William Stein of Binghamton
University in New York , now believe the forest stood in a
flat coastal plain near an ancient shoreline. It was probably buried and
preserved when a river channel shifted, bringing in loads of sand to cover the
forest floor.
Before the forest's death, it was probably chock full of millipedes
and insects, Berry
said. As they grew, the Gilboa trees shed branches, which would have littered
the forest floor and created a perfect habitat for creepy-crawlies.
"I've spent 20 years trying to imagine what these plants were like
as individuals, and yet I really had no conception of them as an ecosystem,"
Berry said.
"Going to Gilboa and sitting in the middle of the forest floor, you could
almost see them growing out of the ground. … The fossil forest came
to life in front of my eyes in a way that has never happened
before."
More broadly, a deeper understanding of the forest helps
paleontologists piece together the ecology of the
very earliest forests on Earth. The Devonian period marks a time when plant
life began to shift from small, scattered vegetation to large-scale forests, Berry said. Plants
remove carbon dioxide from the atmosphere, and during the Devonian forest boom,
carbon dioxide levels may have dropped from 15 times that of today to modern
levels.
The arrival of forests changed the way the whole Earth system worked, Berry said. He and his
colleagues are using the Gilboa site to understand how this ecosystem flourished.
"We've gone from knowing about plants to knowing about a
forest," Berry
said. "That's really been the breakthrough for me."
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