The evidence suggests that warblers use their extremely elaborate songs primarily to attract females, clearly confirming the effect of intersexual selection on the evolution of birdsong.

证据表明，莺主要用它们极其精致的歌声吸引雌性，这清楚地证实了雌雄间选择对鸟类鸣叫进化的影响。

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Although its visual effect is so pronounced, dust is only a minor constituent of the material, extremely low in density, that lies between the stars.

尽管它的视觉效果如此显著，但尘埃只是位于恒星之间的物质的一个次要组成部分，其密度极低。

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That had an interesting and extremely useful side effect.

那有一个有趣和非常有用的负作用。

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But last year sales started to drop due to fears of an extremely rare side effect that might itself cause a deadly heart attack.

FORBES: Study Could Hurt Stent Sales

One problem was that it is extremely difficult to recreate the effect in the laboratory.

ECONOMIST: Recreating the planet's magnetic field in a laboratory

Even though the force acting on the asteroid would be extremely small, the cumulative effect over a week or so should be enough to do the trick.

ECONOMIST: The American Association for the Advancement of Science