Unit A Chapter 2-Fossils Views of the Earth’s Past

Fossils Fossils Traces or remains of living things They can give us clues into the following Climate: weather conditions http://www.youtube.com/watch?v=3rkGu0BItKM Habitat: where they lived Food: what they ate Appearance: what they looked like http://www.youtube.com/watch?v=c_DCP4cLVNg

http://www.youtube.com/watch?v=3rkGu0BItKM

Original Remains Ice-whole organisms have been found in ice Tar-thick oily liquid that preserves whole organisms Amber-Tree Sap-traps insects on trees Think the movie Jurassic Park

T-Rex in Ice

Woolly Mammoth found in ice

Tar Pits

Tar Pit in Downtown LA

Amber-Tree Sap

Fossil Formation Molds and Casts Petrified Wood Carbon Films Shape of organisms remains casts-shape was filled in with liquid rock and took shape http://www.youtube.com/watch?v=SEDfRy6DQns Petrified Wood Stone trees-sediments pour into holes in wood and harden Carbon Films Imprints on rocks of entire animals Trace Fossils-leave evidence Footprints, trails, holes, and even feces left behind

Molds of Fossils

Let’s Make a mold Using your play doh! and the shell. We are going to make an example of a cast Watch as I demonstrate.

Casts of Fossils-the molds or space has been filled in

Let’s Make a Cast Using your play doh! and the shell. We are going to make an example of a cast Watch as I demonstrate.

Petrified Wood

Carbon Prints-Living things leaving behind the carbon in their bodies

Let’s Make an Imprint Using your play doh! and the shell. We are going to make an example of an imprint Watch as I demonstrate.

Trace Fossils-evidence of something that was alive

Let’s Make a model of a trace fossil Using your play doh! and the shell. We are going to make an example of a cast Watch as I demonstrate.

Ice Cores Ice Core-Tubular sample that shows the layers of snow and ice Vertical timeline Ice traps air Contents of air like dust and ash from volcanoes Radiation trapped Thicker layers mean ice ages Thin layers mean warmer temps

Ice Core Samples

http://www.youtube.com/watch?v=zoTXbXsC69k http://www.youtube.com/watch?v=n2Tk5iiVSqc

Dating of Fossils

Geologic Time Scale Divides the earths history into sections Just like in Soc. Studies, the earth itself has a timeline Divided by mass extinctions Mass extinction: 90% of all life on the planet dies. What benefit does this have to the ones who lived? http://www.youtube.com/watch?v=SY3MZ_wNFW8