Transcript Chapter 5: Fossils and Geologic Time

Chapter 5: Fossils and
Geologic Time
Topic 4: The Geologic Time Scale
Geologic Time videos
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animated song
Mr.Parr song
Mr.Parr music video
Earth history in a year's time
Item #1
Based on the radiometric dating of rocks on Earth
and from space (moon rocks, meteorites) the
Earth is estimated to be
4.6 billion
____________________________
years old.
This span of time is known as
geologic
_________________________
time
Item #2
All of earth’s geologic time is divided into
distinct intervals based on major events
(changes) on Earth. These divisions are
described by the _________
______________
Geologic time
scale
Item #3
. The largest divisions of time are called
________________.
We presently live in the
eons
phanerozoic
______________________
eon, which began
550 million
about __________________________
years ago.
This time span is marked by an abundant supply
of different species of life on Earth. This eon is
eras
divided into three _____________
based on major
changes to the profile of life on Earth.
Item #4
The boundaries between eras are marked by
major amounts of _____________________
to
extinction
species. This represents the death of every
member of a species. Many of these events are
linked to global ___________________
change
climate
or catastrophic events such as a meteor impact.
Item #5
paleozoic
The ______________________
era is known
as the age of the “fish” (ancient marine life). It
ended with a mass extinction that killed nearly
90
__________
% of all species around at the
time. Toward the end of this era,
reptiles
____________________,
______________________,
and
amphibians
insects
___________________
began to appear. The
Appalachian mountains formed in North
America during this era.
Note: All major land plants (non-flowering) evolved during this
era.
All time prior to
paleozoic referred to
as “pre-cambrian” era)
Typical paleozoic life
Item #6
mesozoic
The ___________________________
era is
known as the age of the reptiles (including
dinosaurs). Small mammals and
__________________
appeared toward the end
birds
of this era. The Rocky Mountains formed in North
America during this time. This era ended with a
mass extinction that killed about 15-20
____________
% of all species around at the time.
NOTE: Flowering plants and bees appeared late in this era.
Item #7
cenozoic
The ____________________________
era is the
most recent and the one we live in today. It is
known as the age of the
_______________________
and includes the
mammals
last ice age and the formation of the Himalaya
Mountains.