The typed scripts from lesson three “Talking Heads,” will be presented to students. We will readthrough each scene, focusing on vocal techniques: volume, relaxation, articulation, flexibility, and comfort level. This readthrough will lead into a further discussion of the Nebular Theory (Kant and Laplace) and how our own planet was formed based on “The Solar System Evolves” from the eighth grade science text,
Exploring the Universe
(page 58). Several charts, photographs and drawings from
The Big Book of The Earth,
a picture book by Dougal Dixon, will also be shown and briefly commented on to further illustrate our planet’s birth as well as its changeable nature. These will include: the Earth’s concentric layers (pages 12-13); oceanic and continental crust movement (page 16); photo of the separation of the North American plate from the Eurasian plate in Iceland (page 17); the Earth’s plates (page 17); diagram of how moving plates produce mountains, rift valleys and oceans (page 18); andesitic and basaltic volcanoes (pages 20-21); and the mechanism of earthquakes (pages 22-23). Afterward, students will cull data from their science text, “The Past Atmosphere,”
Exploring Planet Earth
(pages 16-18) in order to improvise, sketch out scenes, and perform an in-class mini production for a TV weather show about the atmosphere of four billion years ago to 600 million years ago.
A BREATHING PLANET ¥ WEATHER SHOW OUTLINE
¥ Four billion years ago, the atmosphere consists of methane and possibly ammonia.
¥ By 3.8 billion years ago, sunlight triggers chemical reactions in methane, ammonia and water; nitrogen, hydrogen and carbon dioxide are formed; methane and ammonia break down, but water remains—evidence for life as the product of this chemistry and also influencing it.
¥ Lightweight hydrogen escapes gravity and disappears into space; nitrogen in abundance, along with carbon dioxide and water remain in the atmosphere.
¥ In the upper ancient atmosphere, sunlight breaks down water vapor into hydrogen and oxygen gases; but lightweight hydrogen escapes.
¥ Microscopic organisms form in the depths of the ocean where they are protected from the sun.
¥ Oxygen atoms combine with one another to form ozone; the ozone layer forms about 30 kilometers above the Earth’s surface and becomes an “umbrella” for life on Earth, absorbing most of the harmful ultraviolet radiation from sun.
¥ With the protection of the ozone layer, blue-green bacteria form on or near the water’s surface. They use energy in sunlight to combine carbon dioxide from the air with water to produce food.
¥ Green plants grow on land; intaking carbon dioxide and releasing oxygen during the food-making process. This process is called “photosynthesis” and it happens when green plants and other organisms use sunlight as a source of energy to “cook up” or synthesize carbon dioxide and water into carbohydrates (food—organic compounds that include sugars, starches, celluloses, and gums and serve as a major energy source in the diet of animals).
¥ The oxygen released during this food-making process drastically changes the Earth’s atmosphere. With increased oxygen remaining near the Earth’s surface, the planet is able to support life as we know it today.
¥ 600 million years ago, oxygen increases greatly. The amounts of carbon dioxide and oxygen begin to level off and the composition of the atmosphere remains fairly constant to present day.
Since humans had not been around during the formation of the Earth’s atmosphere, it only makes sense (or nonsense `a la Theater of the Absurd) that the hosts of this weather show would be Prokaryotes, asexual reproducing “bacteria-like life that dominated Earth until the oxygen level increased strongly” and Eukaryotes, the 2.1 billion year old cells that reproduced by sexual means and were the forerunners of “nonbacterial forms of life from fungi to humans” (“The Evolution of the Atmosphere,”
Global Environmental Change
by Karl K. Turekian, pages 57-58).
Students again will work in pairs or small groups in order to sketch out the various weather show components, which are described in the text, “The Past Atmosphere” as mentioned (and outlined) above. Given the theatrical nature of the assignment, students will be given license to present this information as comically or absurdly as they wish. For example, one might personify a prokaryote by having him cough and choke as he describes the deadly methane and ammonia atmosphere of four billion years ago, or in another example, umbrellas could be used as props to demonstrate the ozone layer (odds and ends of costumes and props are always available for students to use in theater class). Each student pair or group will work on a brief presentation and offer their work-in-progress to their classmates for critique.