08/11/12 23:29:41
>>576のつづきです。訳教えて下さい！！
Today there is new evidence for the theory that dinosaurs did not disappear gradually,but that they disappeared quickly and suddenly. This theory is known as the asteroid theory.
According to this theory,an asteroid or a comet hit the earth 65 million years ago and caused a huge dust cloud.
The dust cloud blocked the sun for months. As a result,most of the plants on earth died very quickly and dinosaurs' food supply was destroyed.
Although the asteroid theory itself is not new,evidence for the theory is new.
Scientists found large amounts of iridium in layers of earth that are 65 million years old.
The bones of the last dinosaurs are found in the same layers.
Since iridium is rare on earth but often found in space,an asteroid or a comet may have brought the iridium to earth.
Scientists continue to debate the two theories: the climatic theory and the asteroid theory.
In the future,evidence may be found that supports a totally new theory of why dinosaurs died out.
よろしくお願いします。