Newsademic British English edition 260



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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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