Changing Planet: Past, Present, Future

Lecture 1 – The Deep History of a Living Planet

by Andrew Knoll, PhD
  1.  1.  Start of Lecture One
  2.  2.  Profile of Dr. Andrew Knoll
  3.  3.  Earth's history is recorded in rocks
  4.  4.  North America 20,000 years ago
  5.  5.  How do fossils form?
  6.  6.  How do we know there was an ice age?
  7.  7.  Methods for dating the fossil record
  8.  8.  Reconstructing life from 100 million years ago
  9.  9.  The Cretaceous mass extinction
  10. 10.  What was life like 500 million years ago?
  11. 11.  Earth's history is much older than animal history
  12. 12.  Q&A: How does diversity rebound after mass extinctions?
  13. 13.  Q&A: How do historic warm climates relate to global warming?
  14. 14.  Q&A: How do you know how much 14C was in an animal?
  15. 15.  The tree of life suggests that the deep history of life is mostly microbial
  16. 16.  Microfossils provide a record of microbial history
  17. 17.  Animation: Arctic Island Was a Tropical Island 500 Million Years Ago
  18. 18.  A closer look at the Spitsbergen rocks
  19. 19.  Microfossils show similarities to modern-day cyanobacteria
  20. 20.  The importance of cyanobacteria
  21. 21.  Stromatolites in the fossil record and today
  22. 22.  Lipids as molecular fossils
  23. 23.  Stable carbon isotope ratios show evidence for life
  24. 24.  Life evolved at least 3.5 billion years ago
  25. 25.  Life existed before Earth had atmospheric oxygen
  26. 26.  Animal diversity and size increased with higher oxygen levels
  27. 27.  Summary of the biological history of Earth
  28. 28.  Q&A: What is the evidence placing Archaea close to eukaryotes?
  29. 29.  Q&A: What causes iron to accumulate in large bands?
  30. 30.  Q&A: Can you explain the magnetic evidence for continental drift?
  31. 31.  Q&A: How did O2 level increase lead to greater animal diversity?
  32. 32.  Our fascination with other planets in the solar system
  33. 33.  Mapping the "canals" on Mars
  34. 34.  Popular culture and its fascination with potential life on Mars
  35. 35.  Alfred Russell Wallace: Mars climate is too hostile to support life
  36. 36.  Space exploration increases mapping resolution of Mars
  37. 37.  Evidence for some Martian rocks being deposited by wind
  38. 38.  Evidence of water on Mars
  39. 39.  Geological processes on Earth inform us about past Mars environments
  40. 40.  Chemical analysis reveals the environment on Mars
  41. 41.  Highly acidic water on Earth can harbor life
  42. 42.  High water activity is critical for life
  43. 43.  Martian water activity suggests life could not be supported on Mars
  44. 44.  Mars rover Curiosity: A new chapter of Mars exploration
  45. 45.  Q&A: Does water freeze or boil on Mars?
  46. 46.  Q&A: What caused the atmospheric change on Mars?
  47. 47.  Q&A: How will we continue to look for life on other planets?
  48. 48.  Q&A: What constitutes a reef?
  49. 49.  Credits


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