科学美国人60秒 SSS 2014-09-22
时间：2014-10-21 08:40:30
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（单词翻译）
Sixty-six million years ago, the meteorite1, a rock over six miles wide, slammed into the earth and you know what happened next, the dinos disappeared. but Benjemin Blunder, a planty ecologist at the University of Arizona, says ," consider the picture for a moment."
You have to think not only about the charismatic animals which are walking on the planet but also all the resources on which those animals are depending.
Say, for example, vegetation. Blunder has been giving those overshadowed impact victims their due. After all, more than half the planet's species in temporary North America periched along with the dinosours. And the type of plants that thrived after the impact were different as well. Blunder and his colleagues studied thousands of fossile leaves from North Dokotar, spanning about a million years both before and after the impact. They measured the leaf mass per area, a
proxy2 for how much energy a plant invests in its leaves, and
density3 vein4 s, which indicates how fast growing the leaf is. Sturdy, slow-growing leaves tend to be ever-greens, whereas the flimsy, fast-growing leaves are hall marks of decidous plants. Turns out that after the impact the fossile records have more deciduously looking leaves, suggesting that fast-growing, more
adaptable6 seasonal7 plants beat out the competition after the big hit. The study appears in the journal" Plus Biology". And it kind of made me wonder if we have overlooked another theory for why the dions died out. Maybe they just didn't care for the taste of the
deciduous5 leaves.
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