TPO 75 intergrated writing

How to prevent the invasive sea stars from spreading is the focus of both the writer and the professor. In the writing, three theories, including using a poison named quicklime, introducing parasites, and treating ballast water, have been elaborated. The professor, however, claims that these methods are not practical.

As opposed to the writer’s idea that quicklime could kill invasive sea stars while not hurting other commercial mollusks, the professor states that quicklime will somewhat also put the native sea stars as victims. He advances the theory by saying that when invasive species vanish, as a substitute, the native ones will dive deep into the seafloor, where quicklime accumulates and eventually causes their death.

The professor continues to discredit the writer’s assertion that introducing the parasites, which can damage the reproductive system of male sea stars, will ultimately decrease the number of invasive species, by examining the fact that the parasites cannot completely destroy the reproductive system. In detail, he points out that it is not uncommon that the male sea stars will still mate with females since their reproductive system cannot be fully damaged; otherwise, a large number of eggs – usually more or less 20 million -that a female sea star can produce at a time, making the parasites a total joke.

It is the professor’s third argument that spreading through the ballast water is not the only way for the invasive sea star larvae to colonize other places, which contradicts the view of the writer that by sterilizing the ballast water, new areas will be free from the invasive sea stars. To explore deeper, the professor contends that other objects, such as small ships, and other fishing equipment, would be places that can carry sea star larvae, so as to flourish the invasive species.

An apparent divide exists between the writer and the professor on the method of preventing the spread of invasive sea stars.