Critical Thinking Questions and Answers

Chapter 3

4) Most tsunamis occur in the Pacific Ocean. as indicated by the map in the "Waves That Kill" boxed reading (see p. 62). How would you explain this?

* The pacific basin is almost entirely circled by boundaries of plates and thats why the Pacific Ocean areas frequently have earthquakes, which, will and may cause tsunamis.

Chapter 7

3) A new class of echinoderms, the sea daisies or concentricycloids, was discovered in 1986. They are deep-water animals live in on sunken wood. They are flat and round, looking very much like a small sea star without arms. The also lack a gut. Without ever having seen them, why do you think they were classified as echinoderms, not as members of new phylum? Any Hypotheses as to how they feed or move around?

* I think they were classified as echinoderms because it's like a starfish and how they are structured. I think they drift around like planktons in order to move around and as to how they feed, since it lives on sunken wood maybe it feeds on composed bacteria and dissolved organic material on the sunken wood that they live on.

Chapter 14

2. Scientist predict that the ocean will get warmer and the sea level will rise as a result of an intensified greenhouse effect ("Living in a Greenhouse: Our Warming Earth", p. 406) How might this affect coral reefs?

* If ocean gets warmer as a result of an intensified greenhouse effect, critically thinking, I think the coral reefs will be harmed due to the fact that the sea level rised. So continued global warming will cause reduction of coral reef communities. Although it will vary from one region to another, climate change affects certain coral species in specific regions, such as the ocean getting warmer in higher latitudes, this would probably have the effects of climate change be more harmful than beneficial.

Chapter 8

Chapter 8 critical thinking

1.Why do you suppose there are still some of these jawless fishes around?

* Some still survive but as highly specialized forms as parasites and unusual predators that have not been out

2. A deep-water shark, new to science, is collected for the first time. The specimen is studied in detail, but its stomach is empty. How could you get a rough idea of its feeding habits?

* We can get an idea of its feeding habits by looking at the type of teeth it has to see if its a carnivore or absent teeth as in filter feeders maybe by the relative size and the shape of its mouth.

3. What are the advantages and disadvantages of each situation? Are there any advantages and disadvantages in having an equal number of males and females.

*Having more males than females can be advantageous for the survival of the species in cases where males are more aggressive than females. The relative value of each sex, depends on their behavior. Females can be more aggressive or males can be particularly valuable, if involved in nest making or in the defense of territories. It can be argued, that the best strategy is to maintain an equal number of males and females to prevent a slow down in the reproductive rate of the species in case of increased mortality in one of the two sexes as a result increased predation, or other factors.