Friday, December 5 Warm Up: How many pieces of evidence would you need to believe something is true? Why? AGENDA – Warm-up – 5 min Lecture – 10 min Notes.

Friday, December 5

• Warm Up: How many pieces of evidence would you need to believe something is true? Why?

• AGENDA – • Warm-up – 5 min• Lecture – 10 min• Notes – 10 min• Work time – 25 min

Wegener’s Strange Idea…

I. Who was Dr. Wegener?

a) Alfred Wegener (pronounced “VAY-guh-ner”)

b) Lived 1880-1930c) German scientist

d) Studied many different fields of science to come up with his theory: meteorology (weather & climate), astronomy, biology, geology

e) 1915: published book: “The Origin of Continents and Oceans”

II. Theory of Continental Drifta) Wegener’s hypothesis was that all the

continents were once joined together and have since drifted apart.

*drift* - to wander or to be carried along

b) Wegener called this supercontinent “Pangea” (“all” + “Earth”)

• Stop and think… what does the phrase “Continental drift” mean? Write your own explanation AND draw a picture to remind you of this explanation…

III. Wegener’s Evidence

a. COASTLINES: Today’s continents fit together like puzzle pieces

b. FOSSILS: Similar animal fossils can be found on continents that are very different today

(example- Lystrosaurus in India, Africa, and Antarctica)

c. ROCKS: - identical rock layers

on coast lines of different continents (example- S. America and Africa)

- Mountain chains seem to match up across oceans!

D. CLIMATE: • Tropical fossils found in arctic

• Glacier (giant ice masses) scratches in South Africa (hot today!)

e. Wegener concluded…

At one point in the past, today’s continents must have been:

• joined together• located at different latitudes

IV. HOW & WHY did he think the continents moved?

a) Wegener thought the continents moved through the ocean floor, just like icebreakers move through ice.

b) Wegener couldn’t explain a good reason HOW or WHY the continents moved.

(Mechanism - the way that something happens)

Time-out from lecture….

Thought experiment:• Imagine you knew nothing about gravity…• “Hey! Did you know that the moon is what

makes the ocean levels go higher and lower at different times of day?”

• Would you believe me? Why or why not?

(cont.) Why wouldn’t you believe that?

• “Hey! Did you know that the moon is what makes the ocean levels go higher and lower at different times of day?”

• I didn’t explain a way of HOW that happens. (No mechanism!)

That would be like Wegener saying the continents move, but he doesn’t know why!

Wegener put the pieces together correctly… the continents really were stuck together… actually SEVERAL times in the past… But he couldn’t explain HOW the continents moved.

• “Hey! Did you know that the moon is what makes the ocean levels go higher and lower at different times of day? That’s because the ocean thinks that the moon is its daddy. Every night the ocean wants to hear a bedtime story, so it gets closer to the moon!”

Who’s going to believe me now?

That would be like Wegener saying the continents move, because they are like icebreaking ships cutting through the ocean floor!

(BACK TO THE LECTURE…)

C. Big problems w/ Wegener’s proposed mechanism:

i. Hard rock would be breaking through more hard rock!

ii. Even if continents COULD break through the ocean floor, Wegener couldn’t explain what kind of energy or force was making entire continents move.

d) Without a good mechanism, most geologists rejected Wegener’s idea about continental drift.

(reject= to refuse to accept)

e) To move forward, scientists had to explain HOW THE CONTINENTS MOVED…

Yikes! To Much Information! Brain Overload!

• Read page 18 – 22• COMPLETE page 8 in your PT book. • Complete lab from yesterday

HOMEWORK:Write a 5+ sentence summary of

Wegener’s BIG Idea

V. Conclusion

• It’s still a happy science story!– Wegener used EVIDENCE to propose an

explanation for something that he observed– He used many different fields of science– He made people think…– Other scientists built off of his ideas.– He was actually CORRECT- continents do move…

he just couldn’t explain HOW they move!

Summarize your notes! Due _____

• Highlight or underline the main ideas from these notes – (don’t highlight more than 1/3 of the text!)

• Write a five to eight sentence summary of the big ideas from these notes. – Don’t just list the topics we talked about, but summarize the

facts and ideas you learned – You can write your summary below or attach a separate

sheet of paper• Done? Work on foldable (Wegener’s Strange Idea).

Then read pages 18-29!

Tuesday 01/14/14

• Warm Up: What was Wegener’s Theory called?

• Done? 1. Update your Foldable – Wegener’s theory and

convection. 2. Turn in your letter!

Tuesday – 01/14/14

1. Open you book to page 14. 2. Read pages 14-17.

Wednesday 01/15/14• Warm Up: How do the continents move?

• Done?1. Update your TOC to P-52. Help Mrs. Woodruff pass back papers.

Agenda: - Warm Up / TOC update- Foldable Update- Reading – Sea Floor Spreading & Model- Independent Work Time

Wednesday 01/15/14

• Independent Work Time:- Letter to Wegener (Finish and Turn in)- P-4 Summary (pink sheet – finish and turn in)- Convection current work sheet (P-5) Finish- Done with ALL of this? GREAT JOB! Read pages 26-

29

Thursday 01/16/14

• Warm Up: Explain what a convection current is.

• Done? 1. Start reading silently/individually pages 26 – 29.2. Start working on P-6.