A. ASTONISH B. FASCINATE C. AMAZE D. MARVEL PART 7. READ THE TEX...

10.A. astonish B. fascinate C. amaze D. marvel

Part 7. Read the text and choose the answer (A, B, C or D) which you think fits best according to the

text. (5 points)

Life originated in the early seas less than a billion years after the Earth was formed. Yet another three

billion years were to pass before the first plants and animals appeared on the continents. Life's transition from

the sea to the land was perhaps as much of an evolutionary challenge as was the genesis of life.

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What forms of life were able to make such a drastic change in lifestyle? The traditional view of the

first terrestrial organisms is based on mega fossils-relatively large specimens of essentially whole plants and

animal. Vascular plants, related to modern seed plants and ferns, left the first comprehensive mega fossil

record. Because of this, it has been commonly assumed that the sequence of terrestrialization reflected the

evolution of modern terrestrial ecosystems. In this view, primitive vascular plants first colonized the margins

of continental waters, followed by animals that fed on the plants, and lastly by animals that preyed on the

plant-eater. Moreover, the mega fossils suggest that terrestrial life appeared and diversified explosively near

the boundary between the Silurian and the Devonian periods, a little more than 400 million years ago.

Recently, however, paleontologists have been taking a closer look at the sediments below this

Silurian-Devonian geological boundary. It turns out that some fossils can be extracted from these sediments

by putting the rocks in an acid bath. The technique has uncovered new evidence from sediments that were

deposited near the shores of the ancient oceans-plant microfossils and microscopic pieces of small animals.

In many instances the specimens are less than one-tenth of a millimeter in diameter. Although they were

entombed in the rocks for hundreds of millions of years, many of the fossils consist of the organic remains of

the organism.

These newly discovered fossils have not only revealed the existence of previously unknown

organisms, but have also pushed back these dates for the invasion of land by multi-cellular organisms. Our

views about the nature of the early plant and animal communities are now being revised. And with those

revisions come new speculations about the first terrestrial life-forms.