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An international research team has found evidence of the Earth's earliest forest trees, dating back 385 million years.Upright stumps of fossilised trees were uncovered after a flash flood in Gilboa, upstate New York, more than a century ago. However, until now, no-one has known what the entire trees looked like.
Two years ago, two fossils were found near Gilboa of trees which had fallen sideways, with their trunk, branches, twigs and crown still intact.American researchers called in Dr Christopher Berry of Cardiff University, an expert who has studied tree fossils around the world for the last 17 years. Dr Berry was able to identify the trunks as being of the genus Wattieza, a tree fern-like plant.Small fragments of Wattieza have been found in the past, but there was no direct evidence of how large the plant could grow. The new specimens show that they reached at least 8 metres in height and formed the first known forests on earth.
Dr. Berry said: "This is a spectacular find, which has allowed us to recreate these early forest ecosystems. Branches from the trees would have fallen to the floor and decayed, providing a new food chain for the bugs living below.""This was also a significant moment in the history of the planet. The rise of the forests removed a lot of Carbon Dioxide from the atmosphere. This caused temperatures to drop and the planet became very similar to its present-day condition."Dr. Berry worked with colleagues from Binghampton University, New York and from New York State Museum, which discovered the two trunk fossils. Their findings are published in the April 19 edition of the scientific journal Nature.
62.The finding near Gilboa two years ago is motst probably remarkable because_______。
A)Upright stumps of fossilized trees were found in the same plae two centuries ago.
B)Researchers had a difficult time determing the fossilized trees.
C)The fossilized trees were identified as being of the Wattieza
D)The fossilized trees have their trunk,braches, and crown still remaing good
63. Dr. Berry was called in to ________.
A) lead the international research team
B) study the upright stumps of fossilized trees
C) identify the fossilized trees
D) confirm the fossilized trees
64. What is significant about the discovery of the sossilized Wattieza?
A) Researchers can determine the size of a fully grown tree.
B) No other fossil of Wattiezza has been found before.
C) Researchers can recreate the early forest ecosystems.
D) The plant formed the first known forests in the world.
65.When were the first known forests likely to exist in the world?
A) Before Wattieza appeared on the earth.
B) When Wattieza grew on the earth.
C) After Wattieza disappeared from the earth.
D) Before the earth entered the Ice Age.
66. What happened after the rise of the first forests in the world?
A) Carbon dioxide was removed from the atmosphere.
B) The earth gradually became cold and entered the Ice Age.
C) The ecosystem was gradually changed and become similar to the one at present.
D) A new food chain was formed for bush bugs.
