听写材料1.甲壳虫.txt

that deliver the poison to the leaves, this main cutting is just one method the beattles use to prepare safe meal. Another is by cutting the path all the way across the leaves, to hold the flower cameco, then they simply eat between the vain and the poison. In the past, scientists who study the insect adactiction to plan defence have focus on cameco responseces, that is how the insect can newtrilize out of the poison subsenses produce, what you need about truing drilege is that the beattles is actualy egdeviding a behavrio response to the plants defences reather than the morecomen cameco response.It is only actor a beattle survive the rolling counters with the plants reason that learn how to avoid the poison by chewing through the reason transporting vain of kljiopo, and then get themself the safe meal.However, it can take a beattle an hour and half of careful vain cutting to prepare a small leave that takes only a few minutes to eat,so though the method is effective, it is not very effetion. �����壺���������帴�Ƶ����棩 ��ȷԭ�ģ� This morning I want to tell you about a recent scientific discovery dealing with the relationship between plants and animals. This is about a desert shrub whose leaves can shoot a stream of poisonous resin a distance of six feet. You think it would be safe from all attacks by insects? But a recent study has found one insect, a beetle that can chew its way past the plant's defense system by cutting the main vein that delivers the poison to the leaves. This vein cutting is just one method the beetles used to prepare a safe meal. Another is by cutting a path all the way across the leaves to hold the flow of chemicals. Then they simply eat between the veins of poison. In the past, scientists who studied insect adaptation to plant defenses have focused on chemical responses. That is, how the insects can neutralize or alter the poisonous substances plants produce. What's unique about this chewing strategy is that the beetle is actually exhibiting a behavioral response to the plant's defenses rather than the more common chemical response. It is only after a beetle's survived several encounters with the plant's resin that it learns how to avoid the poison: by chewing through the resin transporting veins on the next leaf it eats. And thus gives itself a safe meal. However, it can take a beetle an hour and a half of careful vein cutting to prepare a small leaf that takes it only a few minutes to eat. So, though the method is effective, it's not very efficient. ����ժ¼�� 1. shrub: n. ��ľ 2. resin: n. ��֬ 3. beetle: n. �׿dz� 4. vein: n. ���� 5. neutralize: v. �к� 6. alter: v. �ı�