小龙虾堪称地球上的终极幸存物种

时间：2012-08-06 05:51:42

（单词翻译:单击）

One of the most invasive species on the planet is able to source food from the land as well as its usual food sources in the water, research from Queen Mary, University of London has found. Scientists analyzed1 the of red swamp（沼泽，湿地） crayfish（小龙虾） in Kenya's Lake Naivasha and found that when the water level of the lake was low, the crayfish found additional food sources on land. The study was published in the journal PLoS ONE  August 3, 2012.

 
Lead author Dr Jonathan Grey from Queen Mary, University of London explained: "These crayfish are incredible survivors2; our research shows they are able to feed off terrestrial plants directly, as well as aquatic3（水生的） plants -- the first study to demonstrate this.
 
"It has significant implications for anyone looking to introduce these species in other areas."
 
The research team looked at the diet of the crayfish through a technique called stable isotope4 analysis, where they used a natural chemical signal of diet in the species' tissues to determine what they were eating.
 
They found a proportion of the crayfish population had left the main lake and were surviving by burrowing5 in hippopotamus6 footprints which left small pools of water. After dark the crayfish clambered out from the footprints and grazed on the surrounding terrestrial plants.
 
"This study demonstrates how the red swamp crayfish is such an extraordinarily7 successful invader," Dr Grey said.
 
The red swamp crayfish has been introduced to multiple locations throughout East Africa from the 1960s to enhance fisheries and to attempt to control populations of snails8 which carry a parasite9 causing river blindness in humans.
 
"While they are useful to counteract10 other harmful species in ecosystems11, they are also extremely damaging to fish populations and the balance of the food web. They eat plants, fish eggs, fly larvae12, snails and leeches13 and since we have now shown that they are able to tap into extra resources from the land, they can sustain higher populations under adverse14 conditions such as low water and could cause more of a problem in a variety of environments than we initially15 thought."

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1 analyzed 483f1acae53789fbee273a644fdcda80     
v.分析( analyze的过去式和过去分词 )；分解；解释；对…进行心理分析
参考例句：
  • The doctors analyzed the blood sample for anemia. 医生们分析了贫血的血样。 来自《简明英汉词典》
  • The young man did not analyze the process of his captivation and enrapturement, for love to him was a mystery and could not be analyzed. 这年轻人没有分析自己蛊惑著迷的过程，因为对他来说，爱是个不可分析的迷。 来自《简明英汉词典》
2 survivors 02ddbdca4c6dba0b46d9d823ed2b4b62     
幸存者，残存者，生还者( survivor的名词复数 )
参考例句：
  • The survivors were adrift in a lifeboat for six days. 幸存者在救生艇上漂流了六天。
  • survivors clinging to a raft 紧紧抓住救生筏的幸存者
3 aquatic mvXzk     
adj.水生的，水栖的
参考例句：
  • Aquatic sports include swimming and rowing.水上运动包括游泳和划船。
  • We visited an aquatic city in Italy.我们在意大利访问过一个水上城市。
4 isotope isotope     
n.同位素
参考例句：
  • The isotope ratio is directly used for comparing oils or gases.同位素比率直接用于比较各种石油或天然气。
  • How to apply a radio isotope?如何运用放射性同位素？
5 burrowing 703e0bb726fc82be49c5feac787c7ae5     
v.挖掘（洞穴），挖洞( burrow的现在分词 )；翻寻
参考例句：
  • What are you burrowing around in my drawer for? 你在我抽屉里乱翻什么？ 来自《简明英汉词典》
  • The forepaws are also used for burrowing and for dragging heavier logs. 它们的前爪还可以用来打洞和拖拽较重的树干。 来自辞典例句
6 hippopotamus 3dhz1     
n.河马
参考例句：
  • The children enjoyed watching the hippopotamus wallowing in the mud.孩子们真喜观看河马在泥中打滚。
  • A hippopotamus surfs the waves off the coast of Gabon.一头河马在加蓬的海岸附近冲浪。
7 extraordinarily Vlwxw     
adv.格外地；极端地
参考例句：
  • She is an extraordinarily beautiful girl.她是个美丽非凡的姑娘。
  • The sea was extraordinarily calm that morning.那天清晨，大海出奇地宁静。
8 snails 23436a8a3f6bf9f3c4a9f6db000bb173     
n.蜗牛；迟钝的人；蜗牛( snail的名词复数 )
参考例句：
  • I think I'll try the snails for lunch—I'm feeling adventurous today. 我想我午餐要尝一下蜗牛——我今天很想冒险。 来自《简明英汉词典》
  • Most snails have shells on their backs. 大多数蜗牛背上有壳。 来自《简明英汉词典》
9 parasite U4lzN     
n.寄生虫；寄生菌；食客
参考例句：
  • The lazy man was a parasite on his family.那懒汉是家里的寄生虫。
  • I don't want to be a parasite.I must earn my own way in life.我不想做寄生虫，我要自己养活自己。
10 counteract vzlxb     
vt.对…起反作用，对抗，抵消
参考例句：
  • The doctor gave him some medicine to counteract the effect of the poison.医生给他些药解毒。
  • Our work calls for mutual support.We shouldn't counteract each other's efforts.工作要互相支持，不要互相拆台。
11 ecosystems 94cb0e40a815bea1157ac8aab9a5380d     
n.生态系统( ecosystem的名词复数 )
参考例句：
  • There are highly sensitive and delicately balanced ecosystems in the forest. 森林里有高度敏感、灵敏平衡的各种生态系统。 来自《简明英汉词典》
  • Madagascar's ecosystems range from rainforest to semi-desert. 马达加斯加生态系统类型多样，从雨林到半荒漠等不一而足。 来自辞典例句
12 larvae w2CxP     
n.幼虫
参考例句：
  • Larvae are parasitic on sheep.幼虫寄生在绵羊的身上。
  • The larvae prey upon small aphids.这种幼虫以小蚜虫为食。
13 leeches 1719980de08011881ae8f13c90baaa92     
n.水蛭( leech的名词复数 )；蚂蟥；榨取他人脂膏者；医生
参考例句：
  • The usurers are leeches;they have drained us dry. 高利贷者是吸血鬼，他们吸干了我们的血汗。 来自《简明英汉词典》
  • Does it run in the genes to live as leeches? 你们家是不是遗传的，都以欺压别人为生？ 来自电影对白
14 adverse 5xBzs     
adj.不利的；有害的；敌对的，不友好的
参考例句：
  • He is adverse to going abroad.他反对出国。
  • The improper use of medicine could lead to severe adverse reactions.用药不当会产生严重的不良反应。
15 initially 273xZ     
adv.最初，开始
参考例句：
  • The ban was initially opposed by the US.这一禁令首先遭到美国的反对。
  • Feathers initially developed from insect scales.羽毛最初由昆虫的翅瓣演化而来。

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