Evolution: The Nature of Science

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Evolution The Nature of Science
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Why is the cow dead?
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Possible explanations

• Sick
• Hungry
• Thirsty
• Bullet (involving a cowboy)
• Lightning strike
• Snake bite
• Old age
• These explanations are testable- you can easily
  gather data to make a conclusion.

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Other Explanations

• Hexed by a witch
• Killed by a demon
• Cursed
• Theses explanations are not testable.
• No precedence
• No data to collect
• No way to confirm or refute

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I. The Goal of Science

1. Science seeks to understand the natural world by
   seeking natural explanations

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II. Observations about Life

1. Life on earth is old
2. Hierarchical (you can make a tree of life)
   structure of life on earth
3. Diversity changes through time
4. Organisms fit their environment (adaptation)

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III. Evidence Fossil Record

• Thanks to radiometric dating methods, like
  radiocarbon, uranium-lead, and potassium-argon,
  scientists are able to date and order both
  fossils and the rock around them.
• The fossil record allows us to develop a timeline
  for life on earth and see important events like
  the generation of oxygen, land colonization,
  Pangaea's division, the adaptive radiation of
  animals, and mass extinctions.