Starting in the 1960s and continuing until the 1980s, sailors in Russian submarines patrolling the North Atlantic and Arctic Ocean would occasionally hear strange sounds. These underwater noises reminded the submarine crews of frog croaks, so they called

Generally speaking, the reading passage has proposed three pieces of hypothesis as possible explanation of the strange sound sailors in Russian submarines heard. The lecturer, nevertheless, remain skeptical about the accuracies in each piece of the hypothesis. The evidence given in the passage is not adequate and reliable at all.

Initially, the passage claims that the sound come from the calls of male and female orca whales during a courtship ritual presenting that orca whales inhabit the same area where the submarines ere picking up the noises. Also, scientists discovered that the sounds detected are similar to orca whales make when trying to attract a male. On the contrary, the lecturer refutes this point by saying that it is not the truth. He asserts that orca whales live on the surface rather than in the deep of the ocean, thus, the sound their sounds cannot be detected by the submarines at the bottom of the ocean.

Additionally, according to the reading, giant squalid may make such strange sounds. Moreover, these animals are difficult to detect due to their soft bodies. Nonetheless, the professor challenge this idea by pointing out that in 1960’s some noise were heard, while in 1980’s these sounds suddenly disappeared. According to the professor, there is no reason for the sounds to diminish since giant squalid still exist in the world.

Ultimately, the reading accounts the noises to stray sound from some military technology, like foreign submarines. The lecturer, however, opposed to this hypothesis by explaining that no submarines can move at such fast speed and change direction so quickly. Plus, the professor asserts that no matter how sophisticated the technology is, we cannot make the sounds of submarine engines such silent. Thus, this theory about the military technology cannot be tenable.