Presentation on theme: "Nature of Science Perspectives on Teaching The Earth’s Crust."— Presentation transcript:
Nature of Science Perspectives on Teaching The Earth’s Crust
Overvie w Session One: Central Themes of Cluster 4 – Planet Earth & Beyond Central Themes of Grade 7 Cluster 2: The Earth’s Crust Historical Aspects associated with the “Living Earth” Teaching of Science Applications Lesson Critique & Planning Break Session Two: Electricity (A24) – Properties & Changes to Materials (A23)
Grade 5Grade 6Grade 7Grade 8 Cluster 0 Overall Skills and Attitudes Overall Skills and Attitudes Overall Skills and Attitudes Overall Skills and Attitudes Cluster 1 Maintaining a Healthy Body Diversity of Living Things Interactions Within Ecosystems Cells and Systems Cluster 2 Properties of and Changes in Substances Flight Particle Theory of Matter Optics Cluster 3 Forces and Simple Machines Electricity Forces and Structures Fluids Cluster 4Weather The Solar System Earth's Crust Water Systems on Earth Cluster 4: Planet Earth & Beyond Topics
Statistics – As If This Isn’t Enough! Poorest country in the Western world – GDP per capita 790 USD – per capita income $2 per day Limited natural resources Referred to as politically the most corrupt country in the world Richest 1% control 60% of the country’s wealth 80% live in poverty 40% of the country has no access to basic health services 225,000 children believed to be in slavery –non-paid work 40% of the country’s income from foreign aid First reference to ‘narcoeconomy’ 80% of graduates leave the country
Our Living Earth Not uncommon for peoples of particular geographical regions to hold ‘perspectives of animism’ in their fascination with spiritual powers associated with geological events – earthquakes, volcanoes Not common to North American First Nations, Metis & Inuit. WHY? Where might these beliefs exist in NA? For our First Peoples - much more explicit within beliefs associated with ‘weather’ - Sila
Maori: It is in their hands we have our being. Rūaumoko god of earthquakes and volcanoes, Tāwhirimātea god of wind and storm and Tangaroa god of the sea.
Indonesian Proverb: As much as we have certainty, we also have uncertainty. That is our life.
Three Levels of Activity At Work In Trying to ‘Make Sense’ of Earth Events The relationship between theory, evidence, and reasoning: THEORY Development - Resolution ________________________________________ Processing InfEvidence Evidence Collected – Experiential Level _______________________________________ Reasoning – Cognitive – Psychological Level
Earth’s Crust Key Aspects of Grade 7 Cluster 4 Composition of the Earth Formation of rocks – nonliving matter- and soil –both living and non-living matter Changes to the Earth – mountains, volcanoes, earthquakes, tsunamis; how do we explain these changes? Resources, Careers and technologies associated with Earth science.
How do we explain these changes? Key slos! 7-4-12 Describe evidence to support the continental drift theory and explain why this theory was not generally accepted by scientists 7-4-13 Describe evidence to support the theory of plate tectonics, the role technology has played in the development of this theory and reasons why it is generally accepted by scientists Your thoughts?
Early Greeks To the ancient Greeks citizens, volcanoes' capricious power could only be explained as acts of the gods – often associated with anger toward human behavior Ancient Greek philosophers proposed many theories to account for the from and origin of the Earth and events including volcanoes and earthquakes. Made attempts to explain natural events removed from a spiritual cause – albeit without understanding the Earth’s composition – the advent of reductionism. For example, Aristotle, speculated that earthquakes resulted from winds within the Earth caused by the Earth's own heat and heat from the sun. Volcanoes, he thought, marked the points at which these winds finally escaped from inside the Earth into the atmosphere.
Tectonic Plates, Yes – but Continental Drift? Hmmm
Continental Drift Two Traditions in Confrontation: Mobilists & Fixists
The Early Mobilists…. The Franco-Italian Antonio Snider- Pellegrini, by 1858 in his volume La création et ses mystères dévoilés had provided a basis for accepting the notion that the Atlantic Ocean had opened up as a consequence of continental separation The fit of these continental coastlines, first enunciated by Francis Bacon in the 17 th century as “cuspidal to the south”, was likely well-recognised in Europe
Setting the Stage... 7-4-12 Describe evidence used to support the continental drift theory, and explain why this theory was not generally accepted by scientists. A. Wegener (ca. 1926)
1: Earth is divided into both continents and oceans Alfred Wegener proposes continental drift (ca. 1912) Alfred Wegener, ca. 1920.
2: The distribution of fossil animals and plants re-enforces the connection-points among the continents
Evidence from Past Climates…. In the modern world glaciers are found near the north and south poles. Deserts are largely found in bands that are parallel to the equator. Extensive coral reef complexes lie along the equator.
Desert deposits and reefs that are several hundred million years old are found in bands that suggest the equator was oriented as shown on the left. If we assume that the poles and equator are fixed, the continents must have been in different positions as shown on the left.
Put it all together, and see that the continents were once connected but have drifted apart by ‘sliding’ over or ‘plowing’ through the ocean floor Driving Force?: Mystery, or centrifugal force, or both?
“This is just stupid..!!” A lack of credibility – a climatologist not a geologist Lack of evidence to support theory Theory not supported nor communicated with an intelligible model What was suggested was not clear to his audience - unconvinced A society that was closed to a ‘mobilist’ model
Counter-Argument “This is just stupid..!!” Sir Harold Jeffreys of Cambridge University, world’s leading geophysicist, declares that “this is geology’s darkest hour” Any force strong enough to ‘push’ a continent over a bed of ocean floor would internally deform the continent instead Geology versus Mathematical Physics
Counter-argument Not all pieces of the continental puzzle really match
Counter-argument Many continental margins don’t even fit well geometrically…
Counter-arguments Even if they fit, so what! Lots of ‘fits’ are possible just by chance!!
Still to Come… 7-4-13 Describe evidence used to support the theory of plate tectonics, the role technology has played in the development of this theory, and reasons why it is generally accepted by scientists.
By Next Wednesday We need to see your lessons in draft. They need to be handed in by Wednesday for feedback. We are available Tuesday & Wednesday. We will try to give you immediate feedback in person.