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If you are wondering where the suggested answers came from, you can review the video and the articles in the ecosystem function section. 

1.     After watching the first tutorial, your friend turns to you and says, “Oh, I see! All interactions within an ecosystem network are the same importance, because all species have the same interactions with other species.” Do you agree or disagree with your friend’s statement? Explain why in 2 or 3 sentences. 

Answer: The statement is incorrect. A complete explanation would mention that interactions between organisms in an ecosystem do not all have the same importance. Some species have a greater influence on the whole network than others, such as the whale fall example in the video. 

2.     Which of the following network diagrams illustrates the most stable ecosystem? Explain your answer in two to three sentences. 

Answer: b. A complete explanation would mention that b has the most connections and interactions among species, and ecosystems with more species and connections are more resistant to disturbances. 

3.     The table below shows the data your team collected while documenting the biodiversity on three islands. Based on these results, which of the islands should be categorized as having the greatest biodiversity, using the criterion of species richness? Explain your answer in 2-3 sentences. 

Answer: Using the criterion of species richness, Island A has the greatest biodiversity, because it has the greatest number of species. A complete explanation would mention that the number of species in an ecosystem determines the species richness, and species richness is a key measure of biodiversity. Species richness is not dependent on the number of individuals within each species. So even though Island C has by far the greatest total number of individuals, it has the lowest number of species and therefore does not have the greatest species richness.

4.     Based on what you saw in the video, explain in 2-3 sentences why the whale in the whale fall scenario is similar to the Google server, in terms of their importance to their networks. 

Answer: A complete explanation would mention that the whale is critically important to its ecosystem network because so much of the ecosystem’s energy flows through the whale. Similarly, if the Google server was removed, a large portion of the internet would not function because such a huge amount of information flows through the Google server. The whale and the Google server are both critically important to their networks, much more so than say a crab or one desktop computer, respectively.