蓬莱蕉的叶子为何多孔?
文章来源:未知 文章作者:enread 发布时间:2013-01-18 08:31 字体: [ ]  进入论坛
(单词翻译:双击或拖选)
Swiss cheese plants' iconic leaves help them to avoid stress, according to a US scientist.

一位美国科学家发现,蓬莱蕉的标志性叶子能帮助它们远离压力。
The
The "monster" leaves can reach up to 90cm long
 
Their familiar hole-riddled1 leaves allow the plants to capture sunlight more regularly, his research suggests.
 
The counterintuitive(违反直觉的) idea explains how such plants can survive in shady rainforests. 
 
Commonly grown as house plants, they are found in the wild from southern Mexico to Colombia.
 
Many theories have been suggested for the unusual perforated(穿孔的) leaves.
 
One is that the holes in the leaves allow the plants to resist hurricane winds, by letting the wind pass through. Another that they allow better temperature regulation or water to run through the plants down to its roots. Some have suggested the holes somehow camouflage2(伪装,掩饰) the plants, hiding them from herbivores.
 
But these ideas have rarely been scientifically tested.
 
Now research by graduate student Christopher Muir at the University of Indiana, in Bloomington, US, suggests the holes are an adaptation to the plants' rainforest habitat.
 
His findings are published in the journal The American Naturalist3.
 
Leaves compared
 
The Swiss cheese plant Monstera deliciosa lives in the dark understory of tropical rainforests. It relies on capturing unpredictable shafts4 on sunlight, known as "sunflecks", in order to photosynthesise for energy.
 
Mr Muir questioned whether the sunflecks could explain the unusual leaf shapes so he used mathematical models to compare leaves with and without holes.
 
He found that both leaf shapes benefit equally from the same amount of sunlight.
 
Although a leaf with holes will miss some sunlight, because it filters through the holes, solid leaves with the same surface area actually take up less space, so their access to sunlight is restricted.
 
Mr Muir's models revealed that a leaf with the same surface area, but riddled with holes, would contact sunlight more regularly because it takes up more space.


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1 riddled f3814f0c535c32684c8d1f1e36ca329a     
adj.布满的;充斥的;泛滥的v.解谜,出谜题(riddle的过去分词形式)
参考例句:
  • The beams are riddled with woodworm. 这些木梁被蛀虫蛀得都是洞。
  • The bodies of the hostages were found riddled with bullets. 在人质的尸体上发现了很多弹孔。 来自《简明英汉词典》
2 camouflage NsnzR     
n./v.掩饰,伪装
参考例句:
  • The white fur of the polar bear is a natural camouflage.北极熊身上的白色的浓密软毛是一种天然的伪装。
  • The animal's markings provide effective camouflage.这种动物身上的斑纹是很有效的伪装。
3 naturalist QFKxZ     
n.博物学家(尤指直接观察动植物者)
参考例句:
  • He was a printer by trade and naturalist by avocation.他从事印刷业,同时是个博物学爱好者。
  • The naturalist told us many stories about birds.博物学家给我们讲述了许多有关鸟儿的故事。
4 shafts 8a8cb796b94a20edda1c592a21399c6b     
n.轴( shaft的名词复数 );(箭、高尔夫球棒等的)杆;通风井;一阵(疼痛、害怕等)
参考例句:
  • He deliberately jerked the shafts to rock him a bit. 他故意的上下颠动车把,摇这个老猴子几下。 来自汉英文学 - 骆驼祥子
  • Shafts were sunk, with tunnels dug laterally. 竖井已经打下,并且挖有横向矿道。 来自辞典例句
TAG标签: plants stress holes
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