Fossils evidence for evolution
Radiometric Dating <ul><li>Radioactivity – a useful phenomena for telling how old fossils are </li></ul><ul><li>some atoms...
We detect these particles and the energy that comes with it as radiation
<ul><li>The process of losing particles is called decay. </li></ul><ul><ul><li>decay causes the atom to become something e...
the original material is called the parent isotope the material it becomes is called the daughter product
What’s the half-life of strontium-90? Answer:  25 years Half-life : the length of time required for 50% of the parent mate...
Rates of decay are specific, constant, and measureable. <ul><ul><li>Which is why they can be used for dating fossils once ...
If a geochemical laboratory determines that the volcanic ash in a sample of siltstone has a ratio of U-235 to Pb of 2:3, h...
about 900 million years old 2+3 = 5  and 2/5 x 100 = 40% ANSWER:
Three main types of fossils: Actual remains Imprints Petrification
Three main types of fossils: <ul><li>Actual remains </li></ul><ul><li>bones </li></ul><ul><li>teeth </li></ul><ul><li>shel...
Three main types of fossils: <ul><li>Actual remains </li></ul><ul><li>bones </li></ul><ul><li>teeth </li></ul><ul><li>shel...
Three main types of fossils: <ul><li>Actual remains </li></ul><ul><li>bones </li></ul><ul><li>teeth </li></ul><ul><li>shel...
Three main types of fossils: Imprints molds or casts in mud, sand, etc. that turn to stone
Simulation of how imprint fossils are formed
Three main types of fossils: <ul><li>Actual remains </li></ul><ul><li>bones </li></ul><ul><li>teeth </li></ul><ul><li>shel...
 
This dragonfly was petrified by calcium carbonate (calcite) that covered its surface. This type of petrification can occur...
Fossils are found in sedimentary rock layers.
 
 
 
Most fossils are dated using a combination of relative dating and radiometric techniques.
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  • Fossils

    1. 1. Fossils evidence for evolution
    2. 2. Radiometric Dating <ul><li>Radioactivity – a useful phenomena for telling how old fossils are </li></ul><ul><li>some atoms emit particles from their nuclei </li></ul>
    3. 3. We detect these particles and the energy that comes with it as radiation
    4. 4. <ul><li>The process of losing particles is called decay. </li></ul><ul><ul><li>decay causes the atom to become something else: </li></ul></ul>uranium-238 lead-206 <ul><ul><li>carbon-14 nitrogen-14 </li></ul></ul><ul><ul><li>potassium-40 argon-40 </li></ul></ul>
    5. 5. the original material is called the parent isotope the material it becomes is called the daughter product
    6. 6. What’s the half-life of strontium-90? Answer: 25 years Half-life : the length of time required for 50% of the parent material to decay into the daughter product.
    7. 7. Rates of decay are specific, constant, and measureable. <ul><ul><li>Which is why they can be used for dating fossils once a standard has been developed. </li></ul></ul>
    8. 8. If a geochemical laboratory determines that the volcanic ash in a sample of siltstone has a ratio of U-235 to Pb of 2:3, how old is the ash?
    9. 9. about 900 million years old 2+3 = 5 and 2/5 x 100 = 40% ANSWER:
    10. 10. Three main types of fossils: Actual remains Imprints Petrification
    11. 11. Three main types of fossils: <ul><li>Actual remains </li></ul><ul><li>bones </li></ul><ul><li>teeth </li></ul><ul><li>shells </li></ul><ul><li>amber </li></ul><ul><li>frozen in ice </li></ul>
    12. 12. Three main types of fossils: <ul><li>Actual remains </li></ul><ul><li>bones </li></ul><ul><li>teeth </li></ul><ul><li>shells </li></ul><ul><li>amber </li></ul><ul><li>frozen in ice </li></ul>
    13. 13. Three main types of fossils: <ul><li>Actual remains </li></ul><ul><li>bones </li></ul><ul><li>teeth </li></ul><ul><li>shells </li></ul><ul><li>amber </li></ul><ul><li>frozen in ice </li></ul>Imprints molds or casts in mud, sand, etc. that turn to stone
    14. 14. Three main types of fossils: Imprints molds or casts in mud, sand, etc. that turn to stone
    15. 15. Simulation of how imprint fossils are formed
    16. 16. Three main types of fossils: <ul><li>Actual remains </li></ul><ul><li>bones </li></ul><ul><li>teeth </li></ul><ul><li>shells </li></ul><ul><li>amber </li></ul><ul><li>frozen in ice </li></ul>Imprints molds or casts in mud, sand, etc. that turn to stone Petrification minerals replace the cellular material and harden to stone
    17. 18. This dragonfly was petrified by calcium carbonate (calcite) that covered its surface. This type of petrification can occur in hot springs limestone caves.
    18. 19. Fossils are found in sedimentary rock layers.
    19. 23. Most fossils are dated using a combination of relative dating and radiometric techniques.

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