Every minute of every day, what ecologist James Carlton calls a global "conveyor belt" redistributes ocean organisms. It’s a planet wide biological disruption that scientists have barely begun to understand.
Dr. Carlton—an oceanographer at Williams College in Williamstown, Mass. —explains that, at any given moment, "there are several thousand [marine] species [traveling].., in the ballast water of ships. " These creatures move from coastal waters where they fit into the local web of life to places where some of them could tear that web apart. This is the larger dimension of the infamous invasion of fish destroying, pipe-clogging zebra mussels.
Such voracious invaders at least make their presence known. What concerns Carlton and his fellow marine ecologists is the lack of knowledge about the hundreds of alien invaders that quietly enter coastal waters around the world every day. Many of them probably just die out. Some benignly
A. being moved to new environments
B. destroying the planet
C. succumbing to the zebra mussel
D. developing alien characteristics
| Every year New Zealanders living in
London can be seen loading up Kombi vans and heading off to experience the
"classic European holiday". The trip usually starts in the north of France,
after crossing the channel from Dover in England to Calais, driving down through
France, over the Pyrenees into Spain, west into Portugal and then across the
Continent to Italy and often beyond. There are numerous reasons young New Zealanders take this rite of passage—as well as seeing all the fantastic sights and tasting the delights of Europe’s food and wine, it’s relatively inexpensive. The Kombi is transport and accommodation all in one, cutting down significantly on costs. There is just one problem. As the Kombis become "antique", these trips are usually punctuated with numerous roadside sessions as the van sits idle, in no hurry to start, w A. France B. England C. Spain. D. Italy 我来回答: 提交
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