Earth Science EOG Review
May 20, 2014
Overview
 Symbiosis
 Earth’s layers
 Plate Tectonics/ Pangaea
 Rock Types
 Law of Superposition
 Fossils
 Relative/Absolute Age
 Evolution/Natural Selection/Adaptation
 Geologic Time Scale
Symbiosis: Relationships between
organisms
 Mutualism: Both benefit (+, +) AKA cooperation
 Commensalism: One benefits, the other is
unaffected (+, 0)
 Parasitism: One benefits, other is harmed (+, -)
 Competition: 2 species fighting for the same
resource (ex. sunlight, food, space, shelter,
mates)
Practice EOG Question
What happens to a population and to competition when there is
a reduction of living space?
A) The population expands and competition intensifies
B) Competition strengthens while the population contracts
C) The population increases as competition decreases
D) Competition weakens and the population decreases
Practice EOG Question
Kudzu vines grow by climbing and wrapping around trees. Trees
covered by kudzu can die because they are starved of sunlight.
What type of relationship exists between the trees and the
kudzu growing on them?
A) Competition
B) Mutualism
C) Parasitism
D) Predator-prey
Plate Tectonics
 Earth’s Lithosphere is made of moving plates
 Convergent Boundary: plates push together 
 Divergent Boundary: plates move apart (divorce)  
 Transform Boundary: plates scrape sideways
Practice EOG Question
What do earthquakes tell scientists about the history of the
planet?
A) Earth’s climate is continually changing
B) The continents of Earth are continually moving
C) Dinosaurs became extinct about 65 million years ago
D) The oceans are much deeper today than millions of years
ago
Pangaea
“Supercontinent”
All continents on Earth
were once joined together
Evidence:
Same fossils on different
continents; tropical plant
fossils in arctic
3 Rock Types
Sedimentary
Rock
Formed by
pressing pieces
together
Metamorphic
Rock
Igneous Rock
Formed from heat Formed from solid
and pressure
magma
Where fossils are
found!
Rock Cycle: changing rocks from one type
to another
Law of
Superposition
Oldest rocks on bottom,
youngest on top
Example of Relative Age
(finding age by
comparing)
Youngest Layer (B)
 Oldest Layer (C)
Practice EOG Question
Scientists find dinosaur fossils in the bottom rock layers of a cliff
and mammal fossils in the middle rock layer of the cliff. Which
could best be concluded from this evidence?
A) Dinosaurs ate plants
B) Dinosaurs were eaten by mammals
C) Dinosaurs lived on Earth before the mammals
D) Dinosaurs and mammals lived at the same time
FOSSILS
 Remains of something once LIVING preserved in
sedimentary rock (ex. Plants, animals, fish)
 Transition Fossil: Shows how species has changed over
time
 Index Fossil: Tells us what time period a rock layer is
from (ex. Trilobite)
Practice EOG Question
1. A scientist finds the bones of a dinosaur. What could help the
scientist determine the approximate age of the dinosaur bones?
A)
The birds living in the area of the bones
B)
The weather conditions in the area of the bones
C)
The kinds of trees living in the area of the bones
D)
The index fossils in the area of the bones
Extra: They are asking for approximate age – is this relative or absolute
age?
Practice EOG Question
How do scientists know that some mountains were once at the
bottom of an ocean?
A) Freshwater rivers flow to the ocean
B) Saltwater fish are found in some mountain streams
C) Dinosaur bones have been discovered in the mountains
D) Marine fossils have been found on the peaks of some
mountains
Determining Age
Relative Age
 Determines age
by comparing
 Ex. “This rock
layer is older than
this rock layer”
 Superposition
Absolute Age
 Tells us EXACT
age
 Uses “carbon
dating” –
measures how
 Half Lives
Geologic Time Scale
Timeline of the history of
the Earth
Organized by Eras and
Periods
Can use fossils and ice
cores to see changes
Natural Selection and Adaptation
 Charles Darwin: Galapagos Islands, Iguanas & Finches
 Natural Selection: Survival of the fittest!
 Those best able to survive, will survive and reproduce
 If you can’t survive in your environment, you DIE!
 Adaptation: When a species changes a behavior to
better survive in their environment
Extinctions
If an organism can’t change or
adapt with their environment,
they become extinct and die.
Dinosaur extinction:
1. Either asteroid or volcano
2. Sky fills with ash, blocking the
sun.
3. Earth temp dropped, killed
many species.
4. Then the dust settled, and
greenhouse gases brought
temps back up.
Variation and
Adaptation
Evolutionary theory founded by
Charles Darwin after visiting the
Galapagos Islands.
The animals that are most suited to
their environment are the ones that
survive and reproduce
You don’t adapt you become extinct
As seen by:
Homologous Structures
Vestigial Organs
Phylogenetic Trees (family trees)
Practice EOG Question
What process is most responsible for the extinction of most
species of plants and animals that have lived on earth?
A) Gene mutation
B) Environmental changes
C) Selective breeding
D) Decrease in reproduction
ICE CORES
 Tell the history of Earth through pollution, volcanic eruptions
and any other material/ fossils that can get trapped in the ice
Tree Rings
 Tell weather patterns and age of a tree. When the rings are
close together that means there was drought and when they
are far apart that means ample rain because the tree grew a
lot that year. 1 ring for each year of life.