Discussion Questions Mar 31

Discussion questions
Mar 31
Gonick 2001

1. What hook does the author use to capture your attention?

The author uses a creative comic style with lots of images and sketches along with short texts that provide a precise information towards the history of the universe.

2. How could you adapt this hook in your own case study?

Images have a great impact on how readers come to understand the material, so I think this form of visuals is effective in keeping the reader drawn to the text while comprehending the material. Animation in particular is somewhat childlike which can make the information more fun to read and follow.

3. Why was the Earth more radioactive four billion years ago?

According to the process of calculating the age of rocks, rocks contain radioactive elements; and when they decay they form into solids (never really disappearing). Also, it appears that the beginning of earth was a pool of chemicals that generated heat. Therefore the calculation of dating rocks suggests that the oldest rocks are as old as the earth.

4. What is remarkable about the fact that the oldest evidence for life is found in the oldest sedimentary rocks—that is, the oldest rocks that can possible contain fossils? (think about it; you may need to look up what sedimentary rocks are)

If the oldest sedimentary rocks (the very top layer of the crust) contained fossils, that can provide not only the time period of when the material existed but evidence of some form of life (animals, plants, etc) in that time.

5. The first mass extinction event in the History of Life was triggered by organisms who changed their environment so quickly, that they couldn’t survive in new environment that they created. Explain the circumstances of this extinction event. Over what time scale did it occur?

The story describes that as algae evolved chloryphyl emerged which created a news ource of energy. As the algae continued to eat it released oxygen which formed the ozone layer. As a result species polluted eachother. It appears to have occured 3 billion years ago.

6. What are some of the advantages of sex (from an evolutionary point of view)?

While asexual organisms reproduced exact copies of themselves, sex beings benefited from adopting various genes from the parents which helped them to survive to the ongoing changes in their environment. Sex was also advantageous in making evolution occur faster. Sex-producing species did not live infinitely.

7. What is a notochord?

A notochord became a protective layer for the central nervous system of a invertebrate; a spine or vertebrae, in other words.

8. One of the keys to evolution is that natural selection modifies features in an ancestor, adapting them to new functions. Explain this point using the evolution of the mammalian ear (see p. 23 of the reading).

From a natural selection point of view, the evolution of the mammalian ear may be understood as a result of adaptation, acclimation, or genetic mutation of a mammal as a means of survival. Competition in hunting, for example, may have triggered this development.

9. Describe three events that occurred in the history of life after the Devonian.

1. Jurassic era: this earlier period of dinosaurs demonstrates how these reptiles came to diverse and evolve. Fairly large species grew even larger, and some smaller species developed as birds. Continents began to separate, however, causing habitats to change and species to drift from each other.

2. Cretaceous period: this is a time of great diversity; the food chain escalated varying from plants to birds to Tyrannosaurus Rex. Something caused a drastic change in this ecosystem, however, in which species on the higher level of the food chain (particularly the larger animals) suffered from a lack of food and other sources. Perhaps their large presence in comparison to the smaller mammals required more energy and effort to survive.

3. Age of Mammals: by this time, continents were positioned much like how we know them today. The remaining mammals that survived from the Cretaceous era populated the land, and from this stemmed a growing diversity of birds, terrestrials, and marine animals. Mammals also began to grow larger and eventually hunted each other. This process created adaptations among different species: some developed defense techniques such as horns and armor; others excelled in speed and outrunning predators. The Miocene era suggests the beginning of the apes which heavily populated the trees. This period leads us into how we come to understand the age of humans.