Transcript 4.6 billion years ago

The geological time scale
Eras and periods
What you will learn………
 How vast the earth’s geological time scale really is
 The different eras and periods in earths history
 You will learn where each of the eras fits on the
geological time scale
 The type of life that existed in each era
 The major events or milestones that took place that
shaped earths geologic history
 Where mankind’s history fits on the time scale and
how very small that time is in comparison to the rest of
earth’s history
Some background history
 Starting from the Big Bang!
 Barenaked Ladies theme song versions
 http://www.youtube.com/watch?v=lhTSfOZUNLo&f
eature=related
Big Bang con’t
 Other cool videos (more comprehensive)
 A Brief History of Earth
 http://www.youtube.com/watch?v=y_jiwmtuenQ&feature=fv
w
Carl Sagan: The cosmos discovers itself
 http://www.youtube.com/watch?v=B1hVx7BsvjU&feature=rela
ted
 http://www.youtube.com/watch?v=iE9dEAx5Sgw
Esoteric/Mind blowing Video (Evolution of Everything)
 http://www.youtube.com/watch?v=kbJ_nIFmFsc&feature=rela
ted
 http://www.youtube.com/watch?v=KbjluE9560Q
How old is the Earth?
about 4.6 billion years old
How long ago did the earth cool enough for water vapor to condense and
form oceans?
about 3.8 - 3.9 billion years ago
4.6 billion yr ago
3.8 billion yr ago
Key dates in the history of Earth
 4.6 billion years ago: earth is formed, along with the other planets
 3.7 billion years ago: earth's crust solidified
 3.6 billion years ago: A cooling process began on Earth
 3.5 billion years ago: first life appears in oceans
 3.25 billion years ago: photosynthesis begins in oceans
 3.0 billion years ago: Clouds formed.
 2.4 billion years ago: oceans contain significant amounts of oxygen
 1.9 billion years ago: Eukaryotic cells (cells with a nucleus) evolved in the oceans
 0.65 billion years ago: first multi-cellular organisms appear
 0.5 billion year ago: Oxygen began to saturate the atmosphere.
 0.5 billion years ago: first land plants with inner vessels
 250 million years ago: mass extinction of 99% of all life
 245 million years ago: Age of Dinosaurs begins
 150 million years ago: Supercontinent breaking up; continents drifting apart
 65 million years ago: Age of Dinosaurs ends with mass extinction of 70% of all life
 3.5 million years ago: First proto-humans appear, in what is now Africa
 100,000 years ago: First Homo sapiens appears
 10,000 years ago: Recorded human history begins
Today’s Project………….
 Break into research teams of 3 to 4
 The teams will record/mark & draw 4.6 billion years of Earths history on
adding machine paper (1cm = 10 million years)
 10cm = 100 million years, 1m = 100cm = 1 Billion Years
 Pre-Cambrian Time (4.6-0.54 B.Y.A): Length = 4.06 BY = 4.06m= ??

406cm
 Paleozoic Era (250 - 540 million years ago): Length = 290 MY = ??

29cm
 Mesozoic Era (65 to 250 m.y.a): Length = 185 MY = ??

18.5cm
 Cenozoic Era (present to 65 m.y.a): Length = 65 MY = ??

6.5cm
 Use WEB resources and your book (213-226)
 Complete the Geologic Time Scale Quick Lab Handout and mark two
period lengths on your time strip as outlined in step 4.
 Do step 5 and decorate your strip with names & drawings of organisms
that lived during each division of time (use pg 213-226 in text for ideas)
Interactive Time Travel……..
 http://science.nationalgeographic.com/science/prehis
toric-world/prehistoric-time-line.html
 http://elearn.stisd.net/mod/resource/view.php?id=24
01
Good research web sites…….
 http://www.fossils-facts-and-
finds.com/geologic_time_line.html
 http://www.historyoftheuniverse.com/tl1.html
 http://www.physci.wsc.ma.edu/young/hgeol/geoinfo/
geohistory.html
 http://www.triassiclegacy.org/Bio_Timeline.html
 http://www.fieldmuseum.org/evolvingplanet/POST/E
P_v8.swf
 http://paleobiology.si.edu/geotime/main/
Time Scales (pg 213)