1. FOSSILS

2. Fossils Is any preserved evidence of an organism
Plants, animals, and even bacteria can form fossils
Not all organisms fossilize. Most organisms decompose before they have a chance to become fossilized.

3. 6 Types of fossils Trace fossil Molds and casts Replacement
Petrified or Permineralized
Amber
Original material

4. 1) Trace Fossils Indirect evidence left by an organism
Examples: Footprints and Burrows

5. 2) Molds and casts A mold is an impression of an organism
A cast is a mold filled with sediment

6. 3) Replacement
Original material of an organism is replaced with mineral crystals

7. 4) Petrified or permineralized
Empty pore spaces are filled in by minerals, such as in petrified wood

8. 5) Amber
Preserved tree sap traps an entire organism

9. 6) Original material
Mummification or freezing preserves original organisms

10. Paleontologist People who study fossils
He or she attempts to read the record of life in rocks.

11. Fossils tell us: Organisms before have evolved from earlier organisms
When species have become extinct
What structures are similar among species (Homologous structures)
Date of when organism/fossil existed

13. Geological Time Scale
A model that expresses the major geological and biological events in Earth’s history

14. What makes a geological time period?
Periods are divisions in an Era
At the end of each time period, an event occurred leading to large percentage of living things becoming extinct
This event is known as Mass Extinction

15. Mass Extinctions
The last mass extinction occurred about 65 million years ago when the last surviving dinosaurs became extinct