Transcript Mass Extictions - Central Square School District

Today
Hand in any work needed.
 Get out a small piece of paper, PUT
YOUR NAME ON IT.
 When bell rings the quiz will start and
you will have 1 minute per question to
answer.

Question 1

List the order the rocks came in
First
Second
Third
Forth
Fifth
Sixth
Question 2

What is the oldest group here?
Question 3

What geologic period did the
placoderm fish mostly live?
Question 4

What minerals are in andesite?
Answers

1.) List the order the rocks came in
 4, 5, 2, 6, 1, 3
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2.) What is the oldest group here?
 Borden group
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3.) What geologic period did the
placoderm fish mostly live?
 Devonian
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4.) What minerals are in andesite?
 Feldspar, Biotite, Amphibole
Vocab
Time scale
 Mass extinction
 Evolution

Geologic Time Scale

Earth was formed 4.6 BYA
(billion Years Ago)
How do we know this?
 How old is the oldest rock
on Earth?

 (look at your ESRT!)
Geologic timeline

Copy this down!
Mass Extinctions

These are events where most or a lot
of living things on Earth were killed.

To go Extinct means to have a whole
species die and nothing is left living
from that species.
Causes of mass extinctions
Meteor impacts
 Global Warming
 Oxygen levels
 Sea level change
 Storms
 Volcanic eruptions
 Possible many more things… can
you think of something?
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5 Major mass extinctions

Cretaceous (65mya)
 62% loss of species caused by impact and flood basalts

Triassic (210mya)
 65% loss of species caused by impact and flood basalt.

Permian (250mya)
 90% loss of species caused by impact, flood basalts, &
global warming.

Devonian (365mya)
 72% loss of species caused by impact.

Ordovician (445mya)
 65% loss of species caused by ice age and sea level
fall (still debated)
Historic Mass Extinctions

One famous one is the K-T extinction.
 Cretaceous and Tertiary periods
 Where the dinosaurs died.

Now?? Humans?
 Global Warming
 Sea level rise
 Changing CO2 level
 Loss of resources
Evolution

What is this?
 The response to environmental changes an
organism that allows it to survive.
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Example:
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?Allergies
Birds beaks
Diseases
Goose bumps
Wisdom teeth
Coccyx (tail bone)
Appendix
Causes

Environmental factors:
 Plate tectonics
 Atmospheric changes
 Physical needs
 Weak links die off..
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All occur over long time frames!
Evidence
Birds beaks
 Whales have a hip bone!?
 Ancient giraffes had shorts necks
 Arms of different animals have
same parts.
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