based on Indiana's Academic Standards, Science,
as adopted by the Indiana State Board of Education, Nov 2000.

numbers refer to the age-appropriate grade-level for the content.

Review

Macro-Evolution

Environmental variability

grades 3: to 4:

• once upon a time,...
  • there were different animals, now known only from fossils
• there was an Ice Age about 2 million years ago
  • Wooly Mammoths
    
  • Saber-tooth Tigers
• the Age of the Dinosaurs (ended 65 million years ago) was tropical
  • T. rex, other (smaller) raptors
    
  • Triceratops
    
  • Pterodactyle
    
  • Brachiosaurus
    
  • Stegosaurus

grades 5: to 8:

• the 2^nd Age of the Dinosaurs (ended 65 million years ago) was tropical
  • T. rex, other (smaller) raptors
    
  • Triceratops, Pterodactyle
• the 1^st Age of the Dinosaurs (ended 175 million years ago), also tropical
  • Brachiosaurus
    
  • Stegosaurus
    
  • Crocodiles
• There is a long-term climate cycle
  • 222 Myr to 220 Kyr BP: ice age
    
  • 220 Myr to 265 Myr BP: tropical period
    
  • 270 Myr to 220 Myr BP: ice age

grades secondary: to college:

• cyclic component
  • short term cycles , for example 11 yr precipitation
    • 3-5 yr dry period
    • 2 yr "transition" period
    • 3-5 yr wet period
    • 2 yr "transition" period
• directional component
  • trend which persists for 100's of years
  • probably long term cycles, for example, temperature
    • 'half' of cycle = increasing trend
    • 'half' of cycle = decreasing trend
    • transitioncle = steady trend

• "residual" (unexplained) component
  • random fluctuations around above cycle(s)

Population changes to remain adapted to changing environment:

grades secondary: to college:

• directional change
  • natural selection drives population change
  • population change continues as long as genetics allows
  • if change continues long enough,
    creature becomes so different, it is new species
    • horses are the best known example
      • dog size, four-toed
      • pony size, three-toed
      • wild horse (resembled Przewalski)
        • modern breeds: [approximately 130 recognized]
          Internation Museum of the Horse, Lexington, KY
          Horse Breeds of the World
          • Belgian
          • Clydesdale
          • Appaloosa
          • Palomino
          • Quarterhorse
          • Pinto
          • Mustang
          • Morgan
          • Shetland Pony, etc...
    • elephants are another example
      • Mastodon
      • Wooly Mammouth
      • Indian Elephant
      • African Elephant
• cyclic change
  • natural selection keeps reversing favored traits
    • alternating between two different favored traits
  • population must remain diverse
  • if reproductive barrier between the two different traits;
    populations will diverge into two species
  • there are few familiar example

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