Day 2 School Activity

LEVEL
Ages: general audiences

RATIONALE
A graphic demonstration of the enormous extent of geologic time compared to recent time.

LENGTH
An hour, in advance, to prepare the roll.
10-15 minutes for demonstration, plus 10 minutes or so to re-roll.

MATERIALS

PREPARATION

  1. 1. On a flat, protected surface, unroll the first sheet or so of the roll. Test the marker(s) for clarity and bleed through. Change markers or gear your writing based on the test. If you wish to draw long, dashed lines to show the eons, eras, and periods, try one on your test sheet. Discard the test sheet(s).
  2. Using the perforations between sheets as a ruler (the first is zero), mark the dates and names of items as listed in the table below.
  3. Re-roll the toilet paper. If it tears, repair with tape.

PROCEDURE
Starting at one end of a long hallway, unroll the toilet paper until you reach the end. Note the varying distances.

Re-roll the model to use again (repair with tape if necessary).

SPACING

Sheets of Toilet Paper Event Geological time (Number of years before present) Comments
0.00Present0
0.0005 Modern man 10,000
0.01 Neanderthal man 100,000
0.03 First use of fire 500,000
0.06 Worldwide glaciation 1,100,000
0.07 Homo erectus 1,300,000
0.08 Linking of North and South America 1,500,000
0.08 Oldest stone tools 1,600,000
0.15 Australopithecus 3,000,000
0.50 Beginning of Antarctic ice caps 10,000,000
0.50 Opening of Red Sea 10,000,000
0.75 Formation of Himalayan Mountains 15,000,000
1.15 Beginning of Tertiary/Neogene period (end Paleogene) 23,000,000
1.25 First evidence of ice at the poles 25,000,000
2.00 Collision of India with Asia 40,000,000
2.50 Early horses 50,000,000
2.50 Separation of Australia and Antarctica 50,000,000
3.00 Early primates 60,000,000
3.00 Opening of Norwegian Sea and Baffin Bay 60,000,000
3.00 Alps form 60,000,000
3.25 Beginning of Tertiary/Paleogene period 65,000,000
3.25 Beginning of Cenozoic Era 65,000,000 "recent life"
3.25 Cretaceous Period, Mesozoic Era end 65,000,000
3.25 Dinosaurs became extinct 65,000,000
4.00 Rocky Mountains form 80,000,000
7.00 Cretaceous Period begins (Jurassic ends) 140,000,000
7.50 Early flowering plants 150,000,000
9.00 Early birds and mammals 180,000,000
10.40 Jurassic Period begins (end Triassic) 208,000,000
11.00 Opening of Atlantic Ocean 220,000,000
12.25 Triassic Period begins 245,000,000
12.25 Beginning of Mesozoic Era (end Paleozoic) 245,000,000 "middle life"
14.00 Final assembly of Pangaea 280,000,000
14.50 Beginning of Permian period (end Carboniferous/Pennsylvanian) 290,000,000
16.25 First reptiles 325,000,000
16.15 Beginning of Carboniferous/Pennsylvanian period (end Mississippian) 323,000,000
18.15 Early trees, formation of coal deposits 363,000,000
18.15 Beginning of Carboniferous/Mississippian period (end Devonian) 363,000,000
20.45 Beginning of Devonian period (end Silurian) 409,000,000
21.50 Early land plants 430,000,000
21.95 Beginning of Silurian period (end Ordovician) 439,000,000
24.50 Early fish 490,000,000
25.50 Beginning of Ordovician period (end Cambrian) 510,000,000
28.50 Early shelled organisms 570,000,000
28.50 Beginning of Cambrian period (end of Precambrian time) 570,000,000 rise of multicellular animals
28.50 Beginning of Paleozoic Era 570,000,000 "ancient life"
28.50 Beginning of Phanerozoic Eon (end Proterozoic) 570,000,000 "visible life" (or 544 million years ago)
35 Early multicelled organisms 700,000,000
40 Breakup of early supercontinent 800,000,000
70 Formation of early supercontinent 1,400,000,000
60 First known animals 1,200,000,000
125 Beginning of Proterozoic Eon (end Archeon) 2,500,000,000 "earlier life"
135 Buildup of free oxygen in atmosphere 2,700,000,000
170 Early bacteria & algae 3,400,000,000
190 Oldest known Earth rocks 3,800,000,000
200 Beginning of Archeon Eon 4,000,000,000
230 Precambrian time begins 4,600,000,000
230 Origin of earth 4,600,000,000

Exercise 2 - Foundations

When a scientist discovers a fossil, she/he obtains evidence of an animal or plant that lived on this planet in the past. During the excavation of the fossil, scientists observe the rock formation in which the fossil was found to obtain clues that may allow them to infer additional information.

Obtain a definition of the words paleontology, fossil, fact, observe, infer, and interpret. Within the context of fossil discovery, discuss and use these definitions in a group setting. Your participation in this may better prepare you to understand a fossil’s hidden truths versus the inferences about the organism that scientists propose based on their investigation of the fossil.

Links

How to Date Rocks
http://www.concord.org/~btinker/GL/web/geology/english/dating_rocks.htm

Graph of Atmospheric Oxygen Through Time
http://en.wikipedia.org/wiki/File:Oxygenation-atm-2.svg

Atmospheric Oxygen
http://www.learner.org/courses/envsci/unit/text.php?unit=1&secNum=6

Carbon dioxide though Geologic Time
http://earthguide.ucsd.edu/virtualmuseum/climatechange2/07_1.shtml