▶ Your Answer :
In the reading passage there is an ample
support for the author's claim that the unique appearance of hammerhead shark
has some special merits. However, the professor in the lecture gives several
reasons as a rebuttal to the author's point.
First, the professor contends that the
hammerhead's head does not strengthen its vision. The fact is, they can have
depth perception only when looking distant objects. However, they have blind
spot directly in front of them and it is a major drawback. As a result, they
cannot identify their prey or other obstacles in front of them. This refutes
the reading passage's claim that the hammerhead's unusual head shape allows the
animal to enhance vision.
Second, the professor argues that the other
sharks with regular pointed head can also detect even very weak scents. For
example, the Great White shark can detect a single drop of blood in an Olympic
sized swimming pool. Therefore, there is no clear evidence that the hammerhead
sharks have a better sense of smell compared to other sharks. This counters the
reading passage's assertion that the unique structure of the hammerhead shark's
head enhances a sense of smell.
Finally, the professor insists that the
appearance of hammerhead shark's head does not enable the animal to turn
quickly. The scientists videotaped the hammerhead shark's behavior and noticed
that they do not use their head for steering. However, they have flexible
backbone compared to the other sharks and it is a real reason to turn fast.
This casts doubt on the reading passage's suggestion that the hammerhead's
wide, flat head acts like an airplane's wing and it allows them to move fast.
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