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Online Lessons for Teachers: Learning Evolution

LESSON 3: 

What Is the Evidence for Evolution?

Back to LESSON 3

Activity 1: Teacher Notes

Activity 2: Evidence for Evolution WebQuest

Activity 2: Teacher Notes

Materials You'll Need:
•  calculator
•  8 1/2" x 11" Paper
•  markers
•  crayons
•  scissors
•  magazines
•  glue

Activity 1: Evolution and Time

Darwin brought several small journals on his voyage on the Beagle. Later he transferred the observations and thoughts from his journals to a larger document that he published under the title The Voyage of the Beagle. You will create a journal entry of a specific geologic time period for planet Earth. Although you cannot really go back in time, you can study fossil and rock records to arrive at an understanding of these ancient environments. In this activity, you will learn more about an ancient environment through your Web research.

Procedures
Part A: Geologic Time Journal
In this activity, you will take on the role of a paleontologist who is investigating a particular period of time in Earth's history. Your teacher may assign a time period, or you can choose one to explore.

Your resources for this exploration are the Deep Time Web activity and the Web Geological Time Machine at the University of California, Berkeley Museum of Paleontology Web site, each of which describes how the Earth has changed over 4.6 billion years.

 Screen grab from the Deep Time Web activity.

Deep Time
(Flash)

1. 

Use these Web resources to explore the Earth's history. You can find out about the geology -- stratigraphy (rock layers) and tectonics (plate movement), transformations and extinctions -- ancient life (fossils), and localities (fossil sites).. The strata can give us information about geologic events, the age of the fossils found, the topography of the area, and the ancient climate.

2. 

Visit your chosen time period, and make a detailed journal entry of what you "see."

3. 

If you have time, you may want to illustrate your journal entry with sketches or pictures from a magazine or Web site. When you are finished with your journal entry, your teacher may use it to assemble a timeline to display in the classroom.

Part B: Happy Birthday, Earth!

How old are you today? The Earth is about 4.6 billion years old. In this activity you will create a "Geologic Birthday Card." To do this, you need to figure out when you were born in geologic terms. In other words, if all of geologic time were compressed into one year, during which time period does your birthday fall? This task involves solving ratio problems. If you need help, see below for an example.

1. 

Divide the age of the Earth by the number of days in a year.

2. 

Next add the number of days from the beginning of the year until your birthday. (Include January 1st and your birthday.)


Number of Days per Month

January

31

February

28

March

31

April

30

May

31

June

30

July

31

August

31

September

30

October

31

November

30

December

31


3. 

Subtract this number of days from the total number of days in a year. Geologic time is recorded in terms of millions of years ago (MYA). It counts back from the present.

4. 

Figure out the equivalent number of years on the geologic time scale.

5. 

Round off to the nearest million years.

6. 

Visit the Deep Time Web activity and the Web Geological Time Machine (see Part A above) to find out the name of the geologic time period that corresponds to this year.

7. 

Now that you know your geologic birthday, use these Web resources to study this time period. Design a birthday card for the Earth at that time. Your card should convey something about that time period -- the environment, the presence or absence of life, the arrangement of continents, and anything else you learn about that time. Be creative. You may want to compose a poem or use pictures from the Web site or a magazine.

8. 

Be prepared to share your card with your classmates or display it in the classroom.

See An Example:

Calculations Based on a November 24th Birthday

1. 

4.6 billion/365 = 12, 602,740 years per day

2.  

31 + 28 + 31 + 30 + 31 + 30 + 31 + 31 + 30 + 31 + 24 = 328 days

3.  

365 - 328 = 37. At the end of the year, the November 24th birthday was 37 days ago.

4.  

(12,602,740 years/day) (37 days) = 466,301,380 years

5.  

466,301,380 rounds to 466,000,000, which can be expressed as 466 MYA or the Ordovician.

 

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