文章来源:未知 文章作者:meng 发布时间:2010-04-14 01:17 字体: [ ]  进入论坛

Ecologists in Australia have successfully trained a critically endangered marsupial1(有袋类动物) – the northern quoll(袋鼬) – to turn its nose up at toxic2 cane3 toads5(蔗蟾) . Their results, including fascinating(迷人的,吸引人的) behavioural video footage, are published today in the British Ecological6 Society's Journal of Applied7 Ecology and could provide conservationists with a vital new weapon in the fight against invasive species. In their new study – inspired by children's fairy tale 'Little Red Riding Hood8' – Professor Rick Shine, Stephanie O'Donnell and Dr Jonathan Webb from the University of Sydney tested whether quolls could be taught to avoid eating cane toads through "conditioned taste aversion(条件性味觉厌恶) " (CTA).

Cane toads are highly toxic when eaten and have driven the northern quoll (Dasyurus hallucatus) – a cat-sized marsupial – to extinction9 in many parts of northern Australia. Cane toads are continuing to spread and will soon invade the Kimberley, one of the quoll's last strongholds(据点,要塞) .

The main problem for predators11(食肉动物,捕食者) like the quoll is that they eat large toads, which usually kill the quolls rather than merely making them feel nauseous(令人作呕的,厌恶的) . Consequently(所以,因此) , most predators do not learn to avoid toads as food.

According to Dr Webb: "I was reading a modern version of 'Little Red Riding Hood' to my kids, and in that story Grandma sews raw onions into the wolf's stomach, so when the wolf wakes up he feels sick and refuses to eat another Grandma again. It dawned on(渐渐明白) me that if we could teach northern quolls to associate sickness with cane toads, we might have a way of conserving12(保护,保存) them."

Working with the Territory Wildlife Park captive breeding and reintroduction programme, the researchers took a group of 62 young quolls and taught half (the so-called "toad4-smart" group) to associate eating a cane toad with feeling sick.

A few days before the quolls were reintroduced to the wild, members of the toad-smart group were fed a small dead cane toad laced with(用……装饰) nausea-inducing thiabendazole(噻苯咪唑) . The cane toad, which weighed less than 2 grams, was not large enough to kill the quoll but the chemical made them feel sick.

To test whether the taste aversion(味觉厌恶) process worked, both groups of quolls were given a small, live cane toad in plastic container to see whether or not they attacked it. Their behaviour was videoed using a hidden camera, and the quolls were then fitted with radiocollars and released.

Dr Webb and his colleagues found that CTA made the quolls less likely to attack the toad in the plastic container and once released into the wild, the toad-smart quolls survived up to five times longer than "toad-naive" quolls.

"Our results show that this kind of approach works. If you can teach a predator10 that cane toads make you sick, then that predator will leave them alone afterwards. As a result, animals like quolls can survive in the wild even in a toad-infested landscape," Dr Webb says.

According to Professor Shine:"The next challenge is to see if we can scale up our results to really make a difference to wild populations of endangered predators like quolls, goannas and bluetongue lizards13. First, we have to check that the aversion we create to cane toads is long-lasting. If it is, the next step is to refine our delivery methods – for example, perhaps wildlife agencies could aerially(空想地) deploy14 'toad baits' ahead of the cane toad invasion front to educate quolls to avoid attacking cane toads before the toads invade."

Conservationists urgently need new approaches to tackling the impact of invasive species, which pose one of the gravest threats to global biodiversity. Particularly hard hit by invasive species has been Australia, which accounts for half of all mammal species extinctions worldwide over the past two centuries.

While invasive species can be eradicated15(摆脱,根除) from small islands, this is rarely possible on larger islands or continents. Long-term control programmes are costly16 and labour-intensive, and reintroduction programmes are of limited use if the threat is still present.


1 marsupial 47zzn     
  • Koala is an arboreal Australian marsupial.考拉是一种澳大利亚树栖有袋动物。
  • The marsupial has been in decline for decades due to urban sprawl from car accidentsdog attacks.这种有袋动物其数量在过去几十年间逐渐减少,主要原因是城市的扩张、车祸和狗的袭击。
2 toxic inSwc     
  • The factory had accidentally released a quantity of toxic waste into the sea.这家工厂意外泄漏大量有毒废物到海中。
  • There is a risk that toxic chemicals might be blasted into the atmosphere.爆炸后有毒化学物质可能会进入大气层。
3 cane RsNzT     
  • This sugar cane is quite a sweet and juicy.这甘蔗既甜又多汁。
  • English schoolmasters used to cane the boys as a punishment.英国小学老师过去常用教鞭打男学生作为惩罚。
4 toad oJezr     
  • Both the toad and frog are amphibian.蟾蜍和青蛙都是两栖动物。
  • Many kinds of toad hibernate in winter.许多种蟾蜍在冬天都会冬眠。
5 toads 848d4ebf1875eac88fe0765c59ce57d1     
n.蟾蜍,癞蛤蟆( toad的名词复数 )
  • All toads blink when they swallow. 所有的癞蛤蟆吞食东西时都会眨眼皮。 来自《简明英汉词典》
  • Toads have shorter legs and are generally more clumsy than frogs. 蟾蜍比青蛙脚短,一般说来没有青蛙灵活。 来自辞典例句
6 ecological IrRxX     
  • The region has been declared an ecological disaster zone.这个地区已经宣布为生态灾难区。
  • Each animal has its ecological niche.每种动物都有自己的生态位.
7 applied Tz2zXA     
  • She plans to take a course in applied linguistics.她打算学习应用语言学课程。
  • This cream is best applied to the face at night.这种乳霜最好晚上擦脸用。
8 hood ddwzJ     
  • She is wearing a red cloak with a hood.她穿着一件红色带兜帽的披风。
  • The car hood was dented in.汽车的发动机罩已凹了进去。
9 extinction sPwzP     
  • The plant is now in danger of extinction.这种植物现在有绝种的危险。
  • The island's way of life is doomed to extinction.这个岛上的生活方式注定要消失。
10 predator 11vza     
  • The final part of this chapter was devoted to a brief summary of predator species.本章最后部分简要总结了食肉动物。
  • Komodo dragon is the largest living lizard and a fearsome predator.科摩多龙是目前存在的最大蜥蜴,它是一种令人恐惧的捕食性动物。
11 predators 48b965855934a5395e409c1112d94f63     
n.食肉动物( predator的名词复数 );奴役他人者(尤指在财务或性关系方面)
  • birds and their earthbound predators 鸟和地面上捕食它们的动物
  • The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》
12 conserving b57084daff81d3ab06526e08a5a6ecc3     
v.保护,保藏,保存( conserve的现在分词 )
  • Contour planning with or without terracing is effective in conserving both soil and moisture. 顺等高线栽植,无论做或不做梯田对于保持水土都能有效。 来自辞典例句
  • Economic savings, consistent with a conserving society and the public philosophy. 经济节约,符合创建节约型社会的公共理念。 来自互联网
13 lizards 9e3fa64f20794483b9c33d06297dcbfb     
n.蜥蜴( lizard的名词复数 )
  • Nothing lives in Pompeii except crickets and beetles and lizards. 在庞培城里除了蟋蟀、甲壳虫和蜥蜴外,没有别的生物。 来自辞典例句
  • Can lizards reproduce their tails? 蜥蜴的尾巴断了以后能再生吗? 来自辞典例句
14 deploy Yw8x7     
  • The infantry began to deploy at dawn.步兵黎明时开始进入战斗位置。
  • The president said he had no intention of deploying ground troops.总统称并不打算部署地面部队。
15 eradicated 527fe74fc13c68501cfd202231063f4a     
  • Polio has been virtually eradicated in Brazil. 在巴西脊髓灰质炎实际上已经根除。
  • The disease has been eradicated from the world. 这种疾病已在全世界得到根除。
16 costly 7zXxh     
  • It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
  • This dictionary is very useful,only it is a bit costly.这本词典很有用,左不过贵了些。
TAG标签: species food weapon toad