1. I. What is Paleontology? The study of past life.
2. I1. Paleontologist Paleontologist scientist who studies fossils and plants from past life and other past ecosystems Studies traces left behind by animals and piece together the conditions under which fossils were formed. 3. III. Uniformitarianism Uniformitarianism the idea that the same geologic processes shaping the Earth today have been at work throughout Earths history. This takes a LONG time! 4. Extra Info! James Hutton was the first to develop the idea of Uniformitarianism in 1788 His theory sparked a scientific debate by suggesting that Earth was much molder than previously thought! 5. Rocks record geological events and changing life forms of the past. We have learned that Earth is much older than anyone had previously imagined Continued There are two ways that we can determine the age of a rock: 1. Relative Dating 2. Absolute Dating 6. IV. Relative Dating 7. Relative dating tells us the sequence in which events occurred, not how long ago they occurred. Chronological order - relational 8. a. Law of Superposition The law of superposition states that in an undeformed, undisturbed sequence of sedimentary rocks, each bed is older than the one above it and younger than the one below it. 9. Undistrubed Rock Layer 10. Distrubed Rock Layer 11. b. Original Horizontality The principle of original horizontality means that layers of sediment are generally deposited in a horizontal position. 12. c. Index fossils Index fossils are used to determine approximate age. Index fossils are widespread geographically, are limited to a short span of geologic time, and occur in large numbers. FOUND IN SEDIMENTARY ROCKS 13. Index Fossils 14. d. Geological Column Geologic column is an ideal sequence of rock layers that contains all the known fossils and rock formations on Earth arranged from oldest to youngest. 15. Ticket out the Door! What is Uniformitarianism?