SHARKS: MAGNIFICENT AND MISUNDERSTOOD
Dr. E. Clark is a famous biologist and professor of zoology at the University of Maryland. In this article, she has described her research on sharks:
“My early experiments with shark behaviour at Cape Haze surprised a great many scientists – including, I must admit, myself. The experiments showed how easily many types of sharks learned to distinguish between right and wrong targets, which is a skill they developed as quickly as laboratory while rats. More recent studies of sharks’ brains, sensory systems, and types of behaviour contradict popular misconceptions of sharks as stupid, unpredictable eating machines, with nothing more than primitive brains and a good sense of smell.
In fact, sharks are as predictable as any animal – even one’s wife or husband – if one takes time to study and get to know them. Those of us who have had an opportunity to dive frequently with sharks do so, knowing that it is far safer to swim with these animals than to drive on an average city street or highway. The last few years have produced exciting new knowledge about sharks.
Barely a decade ago, there were only 250 accepted species; today, that number has climbed by a hundred. Sharks are a great deal more sophisticated than we once thought, and we now know that they have a higher sensitivity to electric fields than any animal ever studied. They have also been shown to orient to Earth’s magnetic field. Sharks can match laboratory white rats in certain learning tests, and they have a surprisingly long retention span. Thus, they are hardly the primitive and senseless creatures that man has mistaken them for.
For the most part, the normal shark diet consists of fishes, mollusks, and crustaceans. Few sharks actually hunt or feed on marine mammals. No shark normally feeds on man. Most shark attacks on humans are bite-and-release or slashing types of actions that suggest warnings rather than attempts to kill. We accept the fact that a dog bites a stranger if the latter invades its territory. Are the rare shark attacks on humans caused by the similar invasion of what the shark considers its territory? When we consider the rarity of shark attacks among hundreds of 5 millions of swimmers each year, we should ask ourselves a moral question: Because we like to swim and dive in an environment unnatural to our species, is it right for us to kill off tens of thousands of harmless inhabitants of that environment to ensure our peace of mind?
We have invented many sports that are more hazardous than going into the sea. When we kill ourselves at these, we blame no one else and simply accept the risks. But when it comes to sharing the sea, v/e insist that sharks take all the risks. With further research we may one day be able to predict sharks’ behaviour with great accuracy. When that day comes, I feel certain we will recognize that sharks present no threat to mankind.”
A. What do the following refer to?
1. ‘a skill1 (line 7):
2. ‘them’ (line 14):
3. ‘do so’ (line 15):
4. ‘our species’ (line 39):
5. ‘that environment’ (line 40):
6. ‘these’ (line 42):
B. Find v/ords in the text which mean the opposite of the following.
1. primitive (paragraph 3):
2. safe (paragraph 5):
C. Find words in the text which mean the same as the following.
1. the period of time that something learnt is kept in memory (paragraph 3) :
2. private area (paragraph 4):
D. Mark the statements as True (T) or False (F).
1. The experiments in Cape Haze showed that one can train sharks.
2. Sharks are animals which have primitive brains with a good sense of smell.
3. Today, there are more than 300 accepted species of sharks.
4. Sharks are sensitive to electric fields but not to Earth’s magnetic field.
5. Sharks eat mainly fish, some mammals and man in order to feed themselves.
6. Sharks rarely attack swimmers.
7. The writer thinks that our peace of mind is more important than sharks’ right to live