剑桥雅思8听力真题原文:Test2—section3(3)

2022-06-01 00:34:16

  

  PROFESSOR: How will you know if Asian bees haveentered Australia?

  GRANT: We're looking at the diet of the bird calledthe Rainbow Bee Eater.The Bee Eater doesn't carewhat it eats,as long as they're insects.But theinteresting thing about this bird is that we are ableto analyse exactly what it eats and that's reallyhelpful if we're looking for introduced insects.

  PROFESSOR: How come?

  GRANT: Because insects have their skeletonsoutside their bodies,so the Bee Eaters digest the meat from the inside.Then they bring up allthe indigestible bits of skeleton and,of course,the wings in a pellet - a small ball of wastematerial which they cough up.

  PROFESSOR: That sounds a bit unpleasant.So,how do you go about it?

  GRANT: In the field we track down the Bee Eaters and find their favourite feeding spots,youknow,the places where the birds usually feed.It's here that we can find the pellets.We collectthem up and take them back to the laboratory to examine the contents.

  PROFESSOR: How do you do that?

  GRANT: The pellets are really hard,especially if they have been out in the sun for a few daysso,first of all,we treat them by adding water to moisten them and make them softer.Then wepull them apart under the microscope.Everything's all scrunched up but we're looking for wingsso we just pull them all out and straighten them.Then we identify them to see if we can findany Asian bee wings.

  PROFESSOR: And how many have you found?

  GRANT: So far our research shows that Asian bees have not entered Australia in any number -it's good result and much more reliable than trying to find live ones as evidence of introducedinsects.

  PROFESSOR: Well,that's fascinating!Thank you.Grant,for those insights.I hope that youmight inspire some of our students here to conduct some similar experiments.

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