A strong wind can be a dangerous thing — sometimes it is powerful enough to knock you off your feet. But to plants, the wind is a source of new life, carrying them or their spores (孢子) thousands of miles. A NASA satellite called QuikSCAT has discovered highways of wind over the Earth's oceans. Scientists believe these invisible roads may explain why many nonflowering plants, such as mosses (苔) and lichens (地衣), grow where they do. The satellite is able to send microwaves (微波) from space to the surface of the ocean. The pattern of signals that come back shows which way the winds are blowing. Using this data, the scientists studied a group of islands in the southern hemisphere (半球), near Antarctica．Winds tend to blow anticlockwise (逆时针) in this region, but there are lots of local differences. When the researchers compared these local patterns to botanical (植物学) data, they found that the wind had an important effect on where species of mosses, lichens, and other nonflowering plants grow. For example, Bouvet Island and Heard Island, share 30 per cent of their moss species, 29 per cent of liverworts (叶苔), and 32 per cent of lichens — even though they are 4,430 kilometers apart. In contrast, Gough Island and Bouvet Island, separated by just 1,860 kilometers of sea, share only 16 per cent of mosses and 17 per cent of liverworts. They have no lichens in common. Ferns (蕨类植物) and flowering plants don't travel as well in the wind, so they don't show the same kinds of distribution (分布) patterns. 小题1:This story is about _____.
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