TPO 34

The lecturer and the reading discuss possible reasons that the Stellers sea cows were extinct. Although the passage claims three theories about the extinction of sea cows, the speaker refutes this idea through several reasons which I will describe in this reporter.

First, the passage points out that the native people who lived in the Siberia, they faced with harsh climate and scare of food; so, they had to overhunt of sea cows, because the sea cows were a suitable food source for native people. The lecturer, in contrast, rejects this by claiming that The sea cows were huge marine mammals, their long and weight were9 meter and ten tones, approximately. Also, the population of the village were small, so a couple of the sea cows were enough for a month. Hence, they did not need overhunting of the see cows.

Furthermore, unlike the passage which states that see cows faced the diminish food source, because of ecological changes near Bering island, and the kelp populations were decreased. The professor argues that it is not true that the kelp population decreased. Because, if the ecological system was changed, it had to influence on other marine animals. For example, whales population also had to decrease. But, we did not have a reporter about the whale population at that time.

Finally, although the reading passage says that European fur trade overhunted the sea cows, and their population were decreased. The speaker disagrees by mentioning that it is true that the sea cows were extinct soon after European fur trade went to Siberian, but the sea cow population and size of them were decreasing before the European fur trade went to Siberia. So, other reasons would be reasons for the declining of see cows population.