摘要：7．In earlier times, cosmetics were . A．never used in milk baths B．never used on the eyes C．never used on the skin D．sometimes harmful to the skin C Have you ever noticed, when looking at a map of the world, that the east coast of South America and the west coast of Africa look as though they might fit together? If you have, you are not alone. In 1965 the English scientist Sir Edward Bullard used a computer to Text the fit of the two continents and found that at an ocean depth of 2000 meters the match was very close indeed. It seems too remarkable to be possible, but there is a lot of evidence to suggest that Africa was once joined to South America. For example, there is a belt of ancient rocks along the east of Brazil which corresponds with the rocks across the South Atlantic in West Africa. There is further evidence that existing land masses were once linked. The remains of a 400-to-500-million-year-old mountain chain has been found running down the eastern part of Greenland, western Scandinavia, and through north-west Scotland and Ireland, into western Canada, eventually finding their way to north-west Africa. Then there is the evidence from life itself. In various parts of the world today the same animals and plants can be found on land masses separated by, in some cases, thousands of miles of oceans. Did they evolveat the same time in two different places? It seems unlikely. Biologists believe that there must have been land bridges which have now sunk beneath the sea. Also fossils found in sedimentary rocks(fossils are the preserved remains of life forms)have allowed geologists to trace the same plants from South America, and Antarctica in rocks perhaps 300 million years old. The ice that is now confined to the polar regions has always been so limited in extent. Indeed, during a period of the Earth’s history known as the permocarboniferousage about 250-350 million years ago there is evidence from the rocks that there were glaciers covering South America, parts of Africa, and India Australia. On the other hand, in the northern hemispherethere were deserts. If the continents were distributedas they are today, it is hard to understand how this could be. So there is considerable evidence to show whole continents moved apart, and naturally many people have tried to discover how and why whole land masses moved.

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