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老托听力1
This morning i want to tell you about a resent
recent scientific discovery dealing with a the relationship between plants and animals
This is about a desert shramp
shrub
whose leaves can shut as
shoot a
stream of poinsons as raisin of distence
poisonous resin树脂 a distanceof six feet
You think it would be safe from all attacks by insinct
insects but the a recent study has found one insinct of beatle
insect ,a beetle
that can chose
chewits way pass pastthe plant decent
defensesystem by cutting the main way
vein that delivers the poinsion
poison to the leaves.
This way
vein 静脉cutting is just one method that beatle use
the beetles used to prepare safe meal.another is by cutting a path all the way across the leaves to hole
hold
the flow of chemicals.
Then they simply eat between the vein to the po
veins of poison
In the past scientists who study the science deciton
studied insect adaptation
to plan desci plant defenses have focused on chemical responses.
That is how the insects can neutralize中和 or alter insect plan
poisonous substances plants
produce,what is unique about this choosing strategry chewing strategy
is that the beelte
beetle is actually exciting
exhibiting a behavior role behavioral response,to the plan`s defenses
rather than the more common chemical response.
It is only after a beetle survive
`s survived
several inconters
encounters
with the plant risen.resin
That it learns
how to avoid the risen
resin
by trying tuing
chewing through the risen
resin transporting veins on the next pleste leave
leaf it eats
.and get thus gives
itself a safe meal.
However it can take a beetle an hour and a half of careful way
vein-cutting to prepare a small list that takes
it only takes a few minutes to eat .
So method
though the is effective it`s not very efficient.
感受:在WPS上改完的~仍然是没有显示啊~唉~有机会在这上面改吧~前提是错的少,,不然在这上面打太费劲了~~这篇因为短~~跟读的比较好吧~~不过这个生词还是不行~~影响了文章理解~~ |