TOEFL Listening Practice: Lecture09
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MP3 – SoundCloud
Answer
- B
- A
- C
- B, D
- A
Transcript
| Professor: | Hi Class! Let’s get started! Today we are going to discuss several theories of a strange phenomenon found in the ocean. We don’t know which theory is correct, but there is a ton of research regarding this topic out there. So, after today’s lecture, I would like each of you to do some research of your own and write a three-page paper discussing these theories along with stating which theory you think is the most likely one. Make sure you give your reasons. Remember the assignment is due next week and counts 10% of the grade. Do not leave it till the last minute. |
| Okay, let’s talk about this strange phenomenon. Between the 1960s and 1980s, sailors who patrolled the North Atlantic and Arctic Ocean in Russian submarines would occasionally hear strange sounds. These underwater noises reminded the crews of the croaking sound of frogs, so the sailors called the sounds “quakers.” To date, these underwater noises have puzzled many oceanographers as they can’t identify where they come from. | |
| One thing they did know is that the sources of the sound seemed to be moving with great speed and agility, so some oceanographers suspected that the strange noises were actually the calls of male and female orca whales during a courtship ritual. In fact, orca whales are known to inhabit these areas where the submarines were picking up the bizarre noises. Orcas have been studied extensively, and the female sounds that are made when trying to attract a male are similar to those that the submarines were detecting. This theory seems plausible at first but is unlikely for two reasons. First, orca whales mostly live near the surface of the water, and the submarines typically remain deep in the ocean and, therefore, they would not have been able to hear the whale sounds from near the surface. Second, when the strange underwater sounds were detected, there was no solid moving objects detected by the submarines’ sonar. So if orca whales were nearby, you think they would have been detected by the Russian sonar. | |
| A second theory is that the sounds are from giant squid. Giant squid are marine invertebrates that live deep in the ocean and prey on large fish. This type of squid is difficult to detect by sonar because of their soft bodies devoid of a skeleton. Giant squid have complex brains. It is possible that they have the ability to emit sound. This theory seems more plausible than the first one, but one critical fact speaks against this squid theory. How do we explain the sound only detected between the 1960s and 1980s? Russian submarines first detected sound in the 1960s, but the sounds disappeared entirely by the 1980s. However, as far as we know, squid have always lived in the ocean where the submarines were patrolling and these creatures continue to live there today. If this sound came from squid, there would be no reason to suddenly stop hearing it after the 1980s. | |
| The third theory is that the sounds were caused by a mysterious aquatic mermaid creature. Well! I don’t want to comment on this because we haven’t even proved the existence of the mermaid. But if you are interested in this theory, there is a documentary about the mermaid on The National Geographic channel. I would recommend that you watch it. | |
| So these are the three theories. Quakers are certainly a very strange phenomenon. Experts still debate what the source of the sound was. No one can be sure exactly what caused the sounds, but these experts cite certain problems with all of the theories shared online and in various periodicals. You can utilize these for your assignment. Remember, do not hand in the assignment late. I will see you next week. |