TPO34 integrated

Both the reading and listening are about the extinction of Steller's sea cows that lived in Bering before 1768. The author believes that there are three possible theories for the extinction. The lecturer challenges  the claims made by the author. He is of the opinion that none of these theories are correct.

To begin with, the author suggests that the indigenous Siberian people over hunted  the Sea cows since they were very nutritious. Consequently the sea cows' population dramatically declined.  The lecturer challenges this specific argument by asserting that these Sea Cows were massive creatures that were nine meters long and weigh around 10 tons. they were enormous that could feed a small Siberian village. In addition, he mentions that the Siberian population was very small and overhunting can not be  the main reason for such extinction.

Secondly, the writer claims that  the disturbance in the ecosystem negatively affected the kelp populations, which were the main food source for the cow seas. Thus, the extinction occurred due to food shortage. The lecturer, however, refutes this point by explaining that If severe ecological changes happened at that time near Bering island, it would affect all the marine life there. In other words, not only the kelp population would be declined but the other animals like whales. In addition, he mentions that there are no reports shown that any other  creature has been affected due to ecological disturbances. Therefore, this theory is not correct and the sea cows had not experienced any food shortages.