Today is Thursday, May 3 DO NOW – Take clicker Take w/s & complete Life changes over time

1. Today is Thursday, May 3 • DO NOW – • Take clicker • Take w/s & complete • Life changes over time

2. Lessons 14 - 15 packets – “Evolution”

3. What Fossils Show Chp. 14-2

4. Fossils • A. Definition • 1. The remains or traces of organisms • that lived in the past • B. Where found • 1. Located in rocks, in tree sap, shells • and other materials

5. II. Types of fossils • A. Skeletons • 1. Dinosaur skeletons are fossil types • 2. Soft material/parts of an organism rapidly decay, • bone and teeth become fossils for millions of • years • B. Sediment • 1. If when an organism does and is buried in mud/dirt • known as sediment and found below water • 2. Over time layers of sediment harden into rock • C. Mold • 1. When trapped remains leave an impression • 2. The mold is an empty space inside the rock • a. materials or water may fill rock and harden • into a cast • 1. the cast resembles the remains that • formed the mold

6. What do we know? • Creatures have changed over time • How do we know this? OBSERVATION Fossil Record

7. What are the remains of the past known as? • Crime scene evidence • Fossils • Records • Crumbs 15 Countdown

8. Which is not a type of fossil? • Sediment • Mold • Teeth • Bone • Sap 15 Countdown

9. Which is NOT a place where a fossil would be found? • Rocks • Ocean • Living tree • Dead tree 10 Countdown

10. The fossils record • A. Paleontologists • 1. scientists who study life in the past, look • for and study fossils • 2. their findings form a fossil record • B. Fossil record • 1. Tells how old fossils are • 2. Tells how organisms have changed • over time

11. What has the fossil record shown us? • Many creatures that lived in the past don’t exist today OBSERVATION Origin of new species

12. What has the fossil record shown us? • The creatures alive today haven’t always been around OBSERVATION Different species lived in the past

13. What has the fossil record shown us? • Many creatures in the past looked like living ones we see today OBSERVATION “Family Tree” Relatives with similar, but not the same traits

14. C. Geological time scale 1. Tells the history of life on Earth 2. Life goes back 3.5 billion years 3. Shows life forms in each 4 time periods

15. The Geologic Time Scale

16. What do we know? • The Earth is very old • How do we know this? TESTING & OBSERVATION Radioactive Dating of the Rocks Life is very old! What’s happened to life during those billions of years?

17. This divides the history into time periods. • Eras • Time zones • Geological time scale • Radioactive dating 15 Countdown

18. Scientists that study the life in the past are called • Biologists • Paleontologists • Scientists • Bone specialists 15 Countdown

19. Radioactive dating can be determined by the • age of the rock • energy given off by the rock • make up of the rock • rock’s environment 15 Countdown

20. Dating fossils • A. Relative age • 1. Fossils can be dated by comparing their • locations in rock • 2. Relative age shows if older or younger than • other fossils • 3. Fossils in lowers areas are older than those • in upper layers – as lower rocks were • formed first

21. Actual age • 1. Tells the numbers of years ago the fossil formed • 2. Use radioactive mineral to determine • a. these minerals give off energy as they • decay into another substance over time • 3. Measured in units called half-life • a. time it takes for ½ the mineral to decay

22. Today is Monday, November 19th • DO NOW – • Take clicker • Take w/s & complete

23. True or false: Evolution can occur in a single organism. • True • False

24. V. Extinction • Fossil record shows some organisms lived and • one time then disappeared • B. When disappeared known as extinction • C. As one species becomes extinct, a new species • appears • D. Mass extinction • 1. Ending of a large new of species at one • time • 2. Dinosaurs and other reptiles became • extinct about 65 million years ago

25. VI. Fossils and evolution A. Fossils show how groups of organisms change over time 1. Evolution of an organism B. Ex – horse 1. 50 million years ago a horse had 4 toes on front foot, less than 48 cm tall (about size of a dog) 2. As it evolved the 4 toes became a hoof and became larger

27. VII. Fossils and living organisms A. Paleontologist learned more about fossils by comparing them to today’s living organisms B. Look for similarities in teeth, structure and bones then compare environments C. By studying they are able to discover relationships

28. Hunting for fossils today • A. Paleontologists still search for fossils today • B. As fossils are formed, they try to fit the info • into the history of life on Earth • C. New techniques and technology help • scientists learn more info from fossils • 1. DNA • a. Compare fossil DNA to living • organism’s DNA • b. Use this info to see how organisms • evolved or the relationships • between organisms

29. Mass extinction • has never happened • is the beginning of life • ends a large species at one time • will never happen again

30. Rocks are measured in units called • rockages • lives • half-life • decayers

31. Rocks can be dated by • the environment • their layer location • the amount of decay

32. ASSIGNMENT: - page 365 # 1 – 5 - w/s 14 - 2