r o p ic a l
fo s s il
forest
Researchers from the UK have
discovered numerous tree fossils.
They were found on Svalbard. This
archipelago, or group o f islands, is
part o f Norway. The islands, which
are in the Arctic Ocean, are roughly
halfway between Norw ay’s northern
coastline and the North Pole. The
researchers say that the trees were
part o f an ancient tropical forest.
From scientific tests, the research
ers worked out that the ancient forest
is 380 million years old. Scientists
believe that the first large plants and
trees started to spread across the land
during a period called the Devonian.
This was between 420 and 360 m il
lion years ago. Therefore, the ancient
Svalbard forest contains some o f the
oldest tree fossils ever found.
Drawing o f what the ancient Svalbard forest m ay
have looked like (M Berry / J Marshall)
The researchers say that the an
cient forest grew near the Equator. A
process known as continental drift
explains why its fossilised remains
are now in the Arctic Ocean. As
long as 400 years ago some people
suspected that the w orld’s conti
nents must have moved or ‘drifted’
apart. They noticed that the outlines
o f the east coast o f South America
and west coast o f Africa look like
pieces o f a puzzle, which fit together.
In 1912, Alfred Wegener, a Ger
man scientist, came up with the idea
o f continental drift. He believed that
the continents were slowly moving
around the Earth. In the 1950s a new
theory, called plate tectonics, meant
that the movement o f the continents
was better understood.
Forest fossils from Svalbard, in Norway, the blue bar
is is five centimetres long (M Berry / J Marshall)
Plate tectonics explain why, and
how, huge pieces o f the Earth’s out
er layer, or crust, move. The Earth’s
crust is like an enormous jigsaw. It
is made up o f huge pieces called
(tectonic) plates. These plates float
on the very hot liquid rock deep be
low the surface. They move slowly
at a speed o f around two centimetres
(0.8 inches) per year.
Svalbard’s fossil forest was main
ly made up o f lycopod trees. The for
est’s trees were about four metres (13
feet) high. They had diamond pat
terns on their trunks. The trees’ leaves
were needle-like. They grew directly
out o f their trunks and branches. The
forest was very dense, as the trees
grew close together. These early trees
were slightly similar to modern-day
palm trees and tree ferns.
In later years, large numbers
o f lycopod trees grew in swampy
areas o f the Earth. Other layers of
sand and rock eventually covered
the places where these huge forests
grew. Then, over many millions of
years, the remains o f the trees and
other vegetation turned to coal.
Scientists believe that early trees,
like those found on Svalbard, helped
to change the Earth’s climate.
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