A huge marine mammal known as Steller’s sea cow once lived in the waters around Bering Island off the coast of Siberia. It was described in 1741 by Georg W. Steller, a naturalist who was among the first European to see one. In 1768 the animal became extinct. The reasons for the extinction are not clear. Here are three theories about the main cause of the extinction.
First, the sea cows may have been overhunted by groups of native Siberian people. If this theory is correct, then the sea cow population would have originally been quite large, but hundreds of years off too much hunting by the native people diminished the number of sea cows. Sea cows were a good source of food in a harsh environment, so overhunting by native people could have been the main cause of extinction.
Second, the sea cow population may have become extinct because of ecosystems disturbances that caused a decline in their main source of food, kelp (a type of sea plant). Kelp populations respond negatively to a number of ecological changes. It is possible that ecological changes near Bering island some time before 1768 caused a decrease of the kelp that the sea cows depend on.
Third, the main cause of extinction of the sea cows could have been European fur traders who came to the island after 1741. It is recorded that the fur traders caught the last sea cow in 1768. It thus seems reasonable to believe that hunting by European fur traders, who possessed weapons that allowed them to quickly kill a large number of the animals, was the main cause of the sea cow’s extinction.
Now I want to tell you about what one company found when it decided that it would turn over some of its new projects to teams of people, and make the team responsible for planning the projects and getting the work done. After about six months, the company took a look at how well the teams performed.
On virtually every team, some members got almost a “free ride”… they didn’t contribute much at all, but if their team did a good job, they nevertheless benefited from the recognition the team got. And what about group members who worked especially well and who provided a lot of insight on problems and issues? Well … the recognition for a job well done went to the group as a whole, no names were named. So it wont surprise you to learn that when the real contributors were asked how they felt about the group process, their attitude was just the opposite of what the reading predicts.
Another finding was that some projects just didn’t move very quickly. Why? Because it took so long to reach consensus; it took many, many meetings to build the agreement among group members about how they would move the project along. On the other hand, there were other instances where one or two people managed to become very influential over what their group did. Sometimes when those influencers said “that will never work” about an idea the group was developing, the idea was quickly dropped instead of being further discussed. And then there was another occasion when a couple influencers convinced the group that a plan of theirs was “highly creative.” And even though some members tried to warn the rest of the group that the project was moving in directions that might not work, they were basically ignored by other group members. Can you guess the ending to this story? When the project failed, the blame was placed on all the members of the group.
Do you agree or disagree with the following statement?
Educating children is a more difficult task today than it was in the past because they spend so much time on cell phone, online games, and social networking Web site.
Use specific reasons and examples to support your answer.
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