1. B-SC 5.5: Students will be able to exemplify evidence in fields of embryology, anatomy, biochemistry, and paleontology that underlies the theories of evolution
THE FOSSIL RECORD

2. PALEONTOLOGY THE STUDY OF FOSSILS
FOSSIL RECORD PROVIDES EVIDENCE OF THE HISTORY OF LIFE ON EARTH

3. The fossil record Shows life on Earth has changed over time.
99% of all species that ever lived on Earth are extinct

5. Relative Dating
Age of a fossil is determined by comparing its placement with that of fossils in other layers of rock

6. INDEX FOSSILS used to compare relative ages of layers of fossils
Needs to have been widespread and only lived for short amount of time

7. Relative dating does not provide information about a fossil’s absolute age

8. RADIOACTIVE DATING
Use of radioactive decay to assign absolute ages to fossils (& rocks)
½ life = time required for ½ radioactive atoms in a sample to decay
½ life of radioactive elements is constant

9. Radioactive Dating
Age of sample calculated based on amount of radioisotopes it contains

10. Useful: carbon in all living things ½ life 5730 years
Older than 60,000 years
Useful: carbon in all living things
½ life 5730 years
Fossils > 60,000 yrs unable to detect
Use radioisotopes K-40  Ar-40 with a ½ life of 1.26 billion years