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

– molds• Shape of organisms remainscasts-shape was filled in with liquid rock and took shapehttp://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=n2Tk5iiVSqc

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

Dating of Fossils

Geologic Time Scale

• Divides the earths history into sections

• Just like in Soc. Studies, the earth itself has a timeline

• Arrange the cards on your desk. Raise your hand when you are ready to be checked.