Name _______________________________________________ Date ___________ Pd ______
Timeline Activity
Objectives:

To understand the concept of a million and a billion

To model the geologic time scale

To use the analytical skills of measurement and scientific notation.
 To compare the dynamic relationship between Earth’s conditions and the diversity of its organisms.
Background: As you learn about past events in Earth history you may be surprised when you hear that something occurred ‘only’ a million years ago. In the context of a human lifetime this is an enormous amount of time. Yet geologists many consider this to be a short time ago when compared to the Earth’s age.
The enormity of geologic time is difficult to understand. One way to help visualize geologic time is to create a time line. Note – while there are slight discrepancies among scientists over the exact dates of certain major events (ie: extinction of the dinosaurs), for the purposes of visualization our dates are accurate.
Remember:
10 9 = 1,000,000,000 1 billion
10
6
= 1,000,000
10
5
= 100,000
10
4
= 10,000
1 million
1 hundred thousand
10 thousand
Materials:

Masking tape or sidewalk chalk

Event notecards (below)


Long sidewalk or football field
Measuring wheels, meter sticks
Procedure
1.
Distribute event cards without years on them to each student
2.
Take students to the field and show them the formation of the Earth (4.6 bya) and today.
3.
Ask students to arrange themselves on the field to represent the sequence of events.
4.
Now gather the students and issue the same event cards with the years on them and ask students to calculate their event using the meter sticks/measurement wheels provided. ( Note: it helps to have a few predetermined distances identified to save time). Warn students not to rely on the correct measurements of others or one wrong student can have a domino effect.
5.
Once students have placed themselves correctly, have them mark their event/location with tape or sidewalk chalk.
6.
Take students on a ‘field trip’ of geologic time, calling out events as they are encountered, briefly discussing each event as you pass. This is a great time to relate the significance of the environmental conditions of the planet to the life found at the time, and what contribution each event had to the development of the Earth as we know it today.

Calculations (for football field):
How do we translate history onto our field? 750 million years ago started the Paleozoic Era. Where would this fall on our field?
7.5 x 10
8
years x (1 yard) = 7.5 x 10
8
=7.5 x (10
5.0 x 10 7 years 5.0 x 10 7 5
8
– 10
7
) = 1.5 x 10
1
= 15 yards
750 million years = 7.5 x 10
8
years
Questions
1. Were you accurate on you approximation? When given the event date, was it earlier or later than you expected?
2. Why do you think it is so hard for humans to visualize a billion years?
2. The universe was formed approximately 13.7 billion years ago. Using the same scale, how far away would this be? Can you find a reference point?
Extensions:
This activity can be done (indoors) with a toilet paper roll indicating the history of Earth with students marking events with marker.
Students can either be asked to predict events with blank cards or can be given premade (calculated) cards and asked to measure. Alternatively, the teacher can pre-identify the locations of the events and ask students to mark the place for the simplest visualization. http://www.eshirts.com/product_images/y/537/154301__35716_std.jpg

Event
A Formation of the Earth
B Oldest known rock
C First single-celled organism
D Age of most continental crust
E First viruses appear
F Blue-green algae (1 st to make O
2
)
G First fungi appear
H First multi-celled organism
I
Precambrian Extinction
(70% of all life wiped out)
J First shellfish appear
K First fish appear
L First true plants appear
M First sharks appear
N First amphibian appear
O First reptile appears
P
Permian-Triassic Extinction
(99% of all life wiped out)
Q Mesozoic Era begins
R First mammal appears
S Age of most oceanic crust
T First known bird appears
U Rocky Mountains formed
V Extinction of the dinosaurs
W First proto-humans appear
X Earliest modern humans appear
Y Last Ice Age
Z Recorded human history begins
Approximate Age
4.6 billion years
4.3 billion years
4 billion years
3.7 billion years
3.5 billion years
3 billion years
1 billion years
700 million years
650 million years
570 million years
510 million years
498 million years
390 million years
375 million years
325 million years
250 million years
245 million years
200 million years
180 million years
160 million years
80 million years
65 million years
3.5 million years
2 million years
20,000 years ago
10,000 years
Distance on Field

st

(First oxygen-producers)

(70% of all life wiped out)

(99% of all life wiped out)

(The Age of the Dinsaurs)

Earliest Modern Humans Appear

Recorded Human History Beings