Mass Extinction Timeline

Procedure:

1. Measure 5 meters of adding machine tape.

2. Draw a line across the adding machine paper 10 cm from each end; this should leave 4.8 meters to draw out the geological time with the 5 major mass extinctions.

10 cm mark10 cm mark

4.8 meters in length

3. Using the following geological information about Earth, your group will construct

a timeline of major eras and periods.

4. Label one of the lines at the 10 cm mark PRESENT. Write the word PRESENT

on one of the short 10 cm side. Make sure this line is correct, because all other measurements will be taken from this line.

5. From the PRESENT- line measure and mark off 1 meter intervals. Make a line on

the tape at each 1-meter mark. These are 1 billion time intervals. The meter mark closest to the PRESENT line should be labeled 1 billion, next line 2 billion, then 3 billion, last line 4 billion. 1 meter = 1 billion years

6. Using a meter stick and starting from the PRESENT line, plot the Eras and Periods

list in table 1. At each Era event, draw a straight line across the tape. Label each vertical Era line as shown in the sample below. Next label the geological Periods. Label each event as shown below, with the number of years and the name of the event. Example: the oldest event listed is the beginning of Earth at 4.5 billion years ago. Measure 450 cm (4m + 50 cm) from the PRESENT line. Draw a line across the tape and label it 4.5 Billion – Beginning of Earth. Eons do not need to be plotted.

Example image:

Table 1 / Geologic Time Scale
Eon / Era / Period / Time (millions of years ago)
Phanerozoic / Cenozoic / Quaternary / 1.8 – present
Tertiary / 65-1.8
Mesozoic / Cretaceous / 145-65
Jurassic / 208-145
Triassic / 245-208
Paleozoic / Permian / 290-245
Carboniferous / 360-290
Devonian / 410-360
Silurian / 440-410
Ordovician / 505-440
Cambrian / 560-505
Precambrian / Proterozoic / 2500-560
Archaean / 3800-2500
Hadean / 4500-3800
Table 2 / Mass Extinctions
Name of Event & Date / Extinction Event / Cause
1 / Ordovician-Silurian extinction
about 439 million years ago / 60% of marine organisms. Ordovician extinction was the second most devastating in earth history / Drop in sea levels as glaciers formed, then by rising sea levels as glaciers melted
2 / Late Devonian extinction
about 364 million years ago / killed 57% of marine organisms / cause unknown
3 / Permian-Triassic extinction
about 251 million years ago / Permian-Triassic catastrophe was Earths worst mass extinction
killing 95% of all species,
estimated 70% of land species - plants and animals / Comet or asteroid impact
Others believe the cause was flood volcanism from the Siberian Traps and related loss of oxygen in the seas
4 / End Triassic extinction
199 - 214 million years ago / Killed 52% of marine genera.
Vertebrate deaths are unclear. / Massive floods of lava eruptions –
triggered the opening of the Atlantic Ocean. The volcanism may have led to deadly global warming.
5 / Cretaceous-Tertiary extinction (K-T event)
65 million years ago / 85% of all species died / Several-mile-wide asteroid hit Yucatan Peninsula in the Gulf of Mexico; other theories - gradual climate change or flood-like volcanic eruptions

7. The 5 major mass extinctions from table 2 need to be plotted using the same

techniques as the previous step. Plot the mass extinction events in red ink or marker. This will make them easier to analyze.

Student Handout

Group ______Date ______Class Period ______

______

______

Analysis

1. Which two events on your tape are separated by the longest duration of geologic time? What is the time between these two events?

______

2. From your tape, determine the duration of each of the following:

a. Hadean Era______billion years

b. Archaean Era______billion years

c. Proterozoic Era ______million years

d. Paleozoic Era______million years

e. Mesozoic Era______million years

f. Cenozoic Era______million years

  1. Which of the eras listed in question 2 was the longest? Which was the shortest?

______

______

4. Dinosaurs lived only during the Mesozoic Era. If geologic time started 4.5 billion years ago, what percentage of geologic time did the dinosaurs exists?

5. From your tape, how many years are between each mass extinction?

a. Ordovician-Silurian extinction to the Devonian extinction______

b. Devonian extinction to the Permian-Triassic extinction______

c. Permian-Triassic extinction to the Triassic extinction______

d. Triassic extinction to the Cretaceous extinction (K-T)______

6. What is the average time between each major mass extinction events?

7. Analysis the data from questions 5 & 6 then predict when the next major mass extinction will occur and what might cause this next mass extinction.

All images have hyperlinks attached

Era / Period
Cenozoic / Quaternary

Tertiary

Mesozoic / Cretaceous

Jurassic

Triassic

Paleozoic / Permian

Carboniferous

Devonian

Silurian

Ordovician

Cambrian

Proterozoic /
Archaean
Hadean