Darwinian Evolution
- Offspring resemble parents - traits passed to next generation
- Imperfect process - variations exist in each generation
- More individuals born than survive to reproduce
- Selects for those who are best 'fit'
- Competition is between members of same species
- Evolutionarily stable strategies (ESS) - Hawk vs Dove (p192)
- Evolution arrives at ESS
- ESS is NOT OPTIMAL OUTCOME
- Applies to stability
- Red Queen Effect - run as fast as possible to stay in same place (Leigh Van Valen p194)
- Same number of frogs & flies, but w/ stickier tongues & slipperier bodies
- Fitness Landscape
- Hills: favorable landscapes
- Valleys: unfavorable (evolutionarily behind)ultiple 'local' peaks may exist
- Co-evolution constantly changes the landscape
- Most successful species become better at evolving
- Punctuated Equilibrium - long intervals of no evolutionary change punctuated by short intervals of dramatic change
- Least fit species most likely to change (die or adapt) - vice versa
- Bak & Sneppen developed evolution game
- Fitness b/w 0 and 1
- Continuously adjusting least fit led to higher overall fitness for landscape
- Amarel & Meyer revised game to include predator & prey
- Found mass extinctions occur obeying a power law, without help of any outside intervention (extinctions w/o meteors)
- Frequent small shocks, occasional large shocks, and no outside shocks all produced the same extinction pattern
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