History of Earth Unit Study Guide
Name:
Earth Systems Science
1. If the entire history of earth was placed into a 24 hour day, how long have humans been in existence? The last
few
of the last
before midnight.
2. The study of the history of the earth must include a study of earth systems science.
3. Earth Systems Science: the study of the global interconnecting web of
,
,
and
systems on earth.
a.
: a group of individual elements that make a whole
b.
: laws that affect matter, energy, and their interaction
c.
: the changing of substances from one chemical form to another
d.
: all living things
e. Summary of earth systems science: Earth has a group of elements working together. These elements
include laws of matter, changes in atoms, and living things. All of these parts working together make up
earth and the history of earth.
Theories of Change on Earth
4. Two theories of change on earth
a.
b.
5. Catastrophism: The history of the earth has been dominated by a series of
a. Catastrophes are
; therefore, catastrophism is not a valid theory
for change of earth over time
6. Uniformitarianism: The laws of nature have not
over
a. Assumption: We can use cause and effect to determine the causes of
b. Scientific finding: Earth's history is dominated by small-scale events typical of the present
c. Laws of Nature include:
i.
ii.
iii.
iv. There are many more laws of nature besides these.
v. These are things that don't change. They occur today as they did billions of years ago
Uniformitarianism/Principal of Superposition
7. Principle of
: the oldest rocks and fossils are found on the
layers of earth, and the youngest rocks and fossils are found on the
layers.
8. Label each layer according to the age of rocks and fossils found in the layer. (Oldest, Middle, or Youngest)
Time
9.
: death of the last individual of a species
10. The
record is a record of changes in plants and animals over millions of
years.
a. Shows the change of life from simple to more complicated forms
Geologic Time
11. Earth's timeline is divided into various units of time.
12.
: longest unit of time
a. Four eons
i.
ii.
iii.
Collectively known as the
Current eon.
: The second longest unit of time
a. Phanerozoic eon has three eras:
i.
ii.
iii.
Current era.
iv.
13.
14.
: the third longest unit of time
15.
: the shortest unit of time
16. The changing of major units of time are often marked by certain events/changes on earth. Often these changes
are
events.
a. The event that marked the change from the Proterozoic eon to the Phanerozoic eon was the evolution
of the first
organisms.
b. The event that marked the change from the Paleozoic era to the Mesozoic era was the extinction of the
and many other marine animals.
c. The event that marked the change from the Mesozoic era to the Cenozoic era was the extinction of the
.
17. Different units of time are marked by the organisms that were alive during that time.
a. The first organisms were prokaryotic and evolved during the
b. The first multicellular organisms evolved during end of the Precambrian Supereon.
c. The Paleozoic era included the age of several different groups of organisms
i. Age of
ii. Age of
iii. Age of
d. The Mesozoic era was the Age of
, including dinosaurs.
e. The Cenozoic era is the Age of
, including humans.
18. The earth's systems are fragile. Changes in living conditions for animals have been numerous throughout earth's
history. Changes in living conditions of animals often lead to
events.
a.
of all organisms that have ever lived have become extinct.
19. The Precambrian Supereon represents
of earth's history.
20. The Phanerozoic eon represents the other
of earth's history.
Precambrian Supereon
21. The Precambrian Supereon is comprised of three eons
a.
eon
b.
eon
c.
eon
22. The Precambrian Supereon occurred from
to
billion years ago. The solar system
formed during this time.
23. At first the earth was a
: a hypothetical whirling gaseous mass within a giant
cloud of gas and dust that rotates around a sun and is believed to give rise to a planet.
24. Formation of the earth and life on earth during the Precambrian Supereon:
a. At first a whirling mass of gases
b. Second: the
layers form. The denser materials moved to the center to form
the core.
c. Third: Cooling of the surface formed earth's
d. Fourth: The earth grew in size from when a
impacted the earth
i. Some of the mass from the protoplanet stayed with the earth, and some was ejected to form
the
.
e. Meteorites impacted the earth and brought
and
f. The atmosphere originates; however, the early atmosphere has no
g. The earliest life begins. These life forms were primitive
. Then after a
long time, prokaryotes formed. These were
, which produced
for our atmosphere. Microbes used
to make oxygen.
h. The earliest fossilized cyanobacteria (prokaryotes) are
billion years old.
i. Towards the end of the Precambrian Supereon the first
life forms evolved.
j. At the end of the Precambrian Supereon, there was an explosion of new animals in the
.
Paleozoic Era (of the Phanerozoic eon)
25. The Paleozoic era was the first era of the Phanerozoic eon. The Paleozoic era contained 7 periods:
a.
Period
b.
Period
c.
Period
d.
Period
e.
Period
f.
Period
g.
Period
26. The dominant organisms were marine
.
27. Many fossils from the Paleozoic era have been found in the
, a site
found on top of a mountain range in British Columbia, Canada.
a.
: a sedimentary rock formed from minerals, mud, and other organic materials,
including dead organisms, that settle out of the water and gather on the ocean floor.
b. These mountains were located under the
surface during the Paleozoic era.
28. Next,
fish evolve.
29. Plants move from the ocean onto
. Increased photosynthesis from plants led to an
increased oxygen concentration in the atmosphere.
30. Dead plants and animals decayed to form
, which
over extremely long periods of time became fossil fuels. This occurred during the Carboniferous period.
31.
evolve.
evolve from fish and invade land.
32. The first
appear, and insects begin to evolved
to
.
Mesozoic Era (of the Phanerozoic eon)
33. The Mesozoic era was the second era of the Phanerozoic eon. The Mesozoic era contained 3 periods:
a.
Period
b.
Period
c.
Period
34. The
were the dominant organisms during the Mesozoic era.
35. The dinosaurs can be divided into two groups based on anatomy (hip structure).
a.
: bird-hipped dinosaurs
i. Examples: Prosauropods, Theropods, Sauropods
b.
: lizard-hipped dinosaurs
i. Examples: Ceratopsians, Ornithopods, Ankylosaurs, Stegosaurs
36. The first birds evolve. They likely evolved from which type of dinosaur? (Think about the shared hip structure)
a.
37.
38.
39.
40.
41.
42.
is the earliest ancestor to modern birds and lived
approximately 150 million years ago.
b. Birds evolved from one species of ornithischians called
.
Similarities between birds and theropods:
a. Foot with
toes
b. Walk on
legs
c. Have
bones. Hollow bones allow birds to
.
d. Have a
, which strengthens the thoracic cage for
.
e. Have a pelvis that points
f. Have
Differences between birds and theropods:
a. Theropod arms are
than those of birds, and theropods had no
b. Differences in the structure of the
c. Modern birds have more pronounced
The first
appear, and the first
plants appear during the
Mesozoic era.
The Mesozoic era ends with a mass
event approximately 65 million years
ago. This event was likely caused by a meteorite impact.
Evidence for a meteorite being the culprit for the Mesozoic era.
a. A layer of
is found across the globe in rock layers dating approximately 65 million
years ago. Iridium is found on
.
b. Dinosaur fossils are found below the layer of iridium, but dinosaur fossils are not found above the layer
of iridium.
The exact cause of the extinction event that ended the reign of the dinosaurs has not been determined. The
cause is likely a combination of factors:
a. The meteorite impact event
b.
c.
43. The extinction event led to the Age of
.
44. Dinosaurs were very successful organisms. As a group, they lived on earth for approximately
years.
million
Cenozoic Era (of the Phanerozoic eon)
45. The Cenozoic era is the third era of the Phanerozoic eon. The Cenozoic era contains 2 periods:
a.
Period
b.
Period
46.
become dominant. The Cenozoic era is known as the age of mammals.
47. Mammals move out to inhabit much of the earth's dry surface, but they still had to hid from huge
called
.
48. Large mammals evolved and preyed upon the Phorusrhacids until they became extinct.
49. Earliest primates appear.
50. Global climate becomes
. The ocean level drops and causes the country of Panama to become
dry land. Panama
South and North America.
a. This causes ecological chaos, because many species from South America move into North America.
Many species from North America move into South America. Extinction of many animals was caused by
this new increased level of
for resources.
51. The first human
appear (ancestors to modern humans)
52. The hominids continue to evolve until modern
appear.