长鼻苍蝇吮食比普通苍蝇更高效-凯发k8官网

长鼻苍蝇吮食比普通苍蝇更高效
文章来源:未知 文章作者:enread 发布时间:2013-12-12 08:18 字体: [ ] 
(单词翻译:双击或拖选)
a long-proboscid fly with an extra-long, tongue-like 1(鼻子) might seem to take extra-long to feed on a flower, but it actually has an advantage over its counterparts with average sized nectar-sipping mouth parts. it can suck up almost all nectar(花蜜) available in a flower in one go(一下子), because it has more efficient suction pumps in its head, says florian karolyi of the university of vienna in austria, about a study he and his team conducted in south africa's namaqualand region. the findings are published in springer's journal naturwissenschaften -- the science of nature. the extremely long, thin proboscis of insects from the genus prosoeca (nemestrinidae) evolved as an adaptation to feeding from long, tubular(管状的) flowers. the fly inserts its proboscis into the flower and uses it like a straw to suck up nectar. a suction pump in its head creates a pressure gradient along the proboscis, which allows nectar uptake. the nectar with the highest sugar content offers the greatest energy reward.
 
biophysical reasoning, however, indicates that the exponential increase of 3 that goes hand in hand with higher sugar concentrations would make it more difficult to transport sugar-rich liquids through a narrow food canal. because proboscis length differs visibly among flies from the same species, karolyi and his team therefore wondered if flies with longer "tongues" spent more time feeding on a flower because they had more trouble sucking up the nectar. this would mean that they 4 more energy in the process of 5 nectar.
 
to study this, the researchers focused on the parasitoid nemestrinid fly genus prosoeca that feeds on nectar of the iridaceae, lapeirousia oreogena. the team captured the insect's behavior on camera, measured the length of its body and proboscis and used x-ray microtomography for 6 of the head muscles. they found the reverse to be true. a longer-proboscid fly sports a more efficient two-part suction pump, while proboscis length and suction pump muscle volume go hand in hand. the fly is thus able to 2 up more nectar in a single visit. this allows the insect to gain a possible advantage over other flies with 7 of an average length.
 
analysis of the long-tongued fly's 8 also suggests that the ancestors of nemestrinidae might have been blood-sucking insects. "flies belong to one of the most important but often underestimated groups of flower-visiting and pollinating insects. our results indicate that the prosoeca species represents a highly adapted and efficient nectar feeder," says karolyi.


点击收听单词发音收听单词发音  

1 x1qzn     
n.(象的)长鼻
参考例句:
  • its proboscis has got stuck to a lot of pollen.它的喙上粘了很多花粉。
  • it hovers in front of the flower,using its proboscis to look for nectar. 它在兰花前面飞来飞去, 用喙寻找花蜜.
2 oxawv     
v.小口地喝,抿,呷;n.一小口的量
参考例句:
  • she took a sip of the cocktail.她啜饮一口鸡尾酒。
  • elizabeth took a sip of the hot coffee.伊丽莎白呷了一口热咖啡。
3 ehpwf     
n.粘度,粘性
参考例句:
  • the viscosity shows a rather pronounced variation with temperature.温度对粘度的影响十分明显。
  • the reciprocal of viscosity is known as fluidity.粘度的反意就是流动性。
4 39b2ea06557590ef53e0148a487bc107     
v.花费( expend的过去式和过去分词 );使用(钱等)做某事;用光;耗尽
参考例句:
  • she expended all her efforts on the care of home and children. 她把所有精力都花在料理家务和照顾孩子上。
  • the enemy had expended all their ammunition. 敌人已耗尽所有的弹药。 来自《简明英汉词典》
5 chmxz     
n.集会,聚会,聚集
参考例句:
  • he called on mr. white to speak at the gathering.他请怀特先生在集会上讲话。
  • he is on the wing gathering material for his novels.他正忙于为他的小说收集资料。
6 02de25420938593f7db7bd4052010b32     
(正式的)调查( investigation的名词复数 ); 侦查; 科学研究; 学术研究
参考例句:
  • his investigations were intensive and thorough but revealed nothing. 他进行了深入彻底的调查,但没有发现什么。
  • he often sent them out to make investigations. 他常常派他们出去作调查。
7 050ca596aead0aee7724db45565345eb     
n.(象等的)长鼻( proboscis的名词复数 );(昆虫等的)喙
参考例句:
8 cwgzh     
n.解剖学,解剖;功能,结构,组织
参考例句:
  • he found out a great deal about the anatomy of animals.在动物解剖学方面,他有过许多发现。
  • the hurricane's anatomy was powerful and complex.对飓风的剖析是一项庞大而复杂的工作。
上一篇: 下一篇:
tag标签: head food pump
发表评论
请自觉遵守互联网相关的政策法规,严禁发布色情、暴力、反动的言论。
评价:
表情:
验证码:点击我更换图片
最新评论
网站地图