Geologic Time & Macroevolution

Geologic Time & How We Know About the Past

  • Mass Extinctions PhD comic … “How palaeontology works”
  • Law of Superposition “New layers form on top of old layers…most of the time”
  • Official Geologic Time Scale from the Geological Society of America (with points of interest from me listed below)
    • Pleistocene EpochHomo sapiens emerged as a species (Only 0.2 MYA) – begins 2.6 MYA
    • Neogene Period: Common ancestor of humans and all modern and extinct Great Apes – begins 23 MYA
    • Cenozoic Era: “Age of Mammals” – begins 65 Million Years Ago (MYA)
    • Triassic Period: First dinosaurs and mammals –  begins 252 MYA
    • Devonian Period: “Age of Fishes” with widespread diversification – begins 419 MYA
    • Ordovician Period: Plants make it to land – begins 485 MYA
    • Cambrian Period: Rampant diversification of life – begins 450 MYA
    • Archaean Eon: First living organisms – begins 4 Billion Years ago (BYA)
  • Age of the Earth – the technical bits from the USGS
  • Climate Change XKCD comic – funny but fairly accurate, starts ~22000 years ago.
  • Evidence of Recent Global Climate Change
  • Ice Cores from NASA “Why we know the earth used to be cold/hot/meh in the past”

Unusual Organisms & General Principles of Evolution

Evolution of Humans