In the sets of material, both the reading and listening focus on the camouflage mechanism whether or not helping zebra defense themselves. But the listening casts doubt on the reading at three points.
At the first point, the writer contends that white and black stripes of zebra’s coat may make its predators have optical illusion and misjudge the distance between zebra and the predator. However, the lecturer has a different opinion. He claims that through a lot of observation, hunting zebra is a long process. Instead of catching a zebra in one bound, predators like lions usually pursue their prey until their victims are too tired to run away. At this time, the lions will swarm and feed on their prey.
Secondly, according to the reading, when zebras gather together in a herd, it is difficult for their predator to pick out an individual from its herd. But, the speaker totally opposes that argument. He points out that this theory is only effective if zebras gather closely together. But such cooperation is easily broken down. Because each zebra tends to defense itself. When predators appear and go around zebra herd, zebras will panic and flee their herd. Therefore, the purpose to protect the young, small or injured zebra is over. Predators can pick any one they want. Lastly, with regard to the ability to camouflage with other color in grasslands, the reading claims that the combination between the colors of zebra’s coat and grasses helps zebras be unnoticed by its predators. In contract, the professor states that this argument is opposite to the previous one that zebras camouflage by standing together in an open and wide plain. Furthermore, scientists have no evidence to prove that this activity can divert the attention of predator away and save the life of zebra.
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