Evolving "elementary sight" strategies in predators via Genetic programming

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Evolving "elementary sight" strategies in
predatorsviaGenetic programming

• ICBV Project
• 20.2.07
• Lior Becker

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Goals

• Witness the evolution of the predator "strategy".
• Imitate the evolution of the parts in the brain
  that handle the visual informal interpretation.
• Try to understand the development stages in the
  strategy.
• Try to analyze the usage of the photoreceptors as
  part of the brain function.
• Test if the development of sight strategy is a
  complex process or can be emulated in a computer.
  

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What is Genetic programming ?

• Bio-Inspired
• Inspired by Darwins evolutionary
• principles
• J.Koza style

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Charles DarwinPrinciples

• Competition
• Variation
• Overproduction
• Survival of the fittest

Population adaptation
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Genetic programming

• Main algorithm
• Generate the initial population
• Fitness evaluation
• Create new generation
• Selection
• Cross Over
• Mutation
• Repeat until stop condition

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Genetic programming Individual Representation

• Individual is a Scheme-Like Function
• Represented as a tree (AST)

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Genetic programmingRecombination - cross over
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Predator strategy through GP

• World simulator
• Predator
• Prey
• Process of work

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Predator

• GP
• Brain function
• Undeveloped eye
• 15 photoreceptors
• Moving ability
• Fitness catching prey

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World simulator Prey

• WORLD
• 2D world
• 100100 Matrix
• Predator and prey can be at any location

• PREY
• Static prey
• Straight Line prey
• Circle prey
• Random prey

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Process of work

• 4 Experiments
• Evolving 51 generations, different preys
• Test cases unlearned preys
• Plot fitness through time
• Recording movies
• Function analysis

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Results straight Line prey
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Results test case

• Test Case
• Why is it important ?

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Results Fitness vs. generations

• Improvement
• population adaptation

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Results Function

• (IFLTE
• (IFLTE P6 (PROGN2(IFLTE P3 P11 P13 P13
  )(IFLTE P2 MAXPP MF P5 ))
• (PROGN2 P4 P6 )(IFLTE AP MB P5 MB ))
• (PLUS MAXPP P15 )
• (PLUS(IFLTE P3 P1 MF P14 )(IFLTE TR MF P1
  P12 ))
• (PROGN2(PLUS P12 P10 )(PLUS P11 TL )))
• Redundancy ? Dead code.

(IFLTE (IFLTE P6 (IFLTE P2 MAXPP MF P5) P6
(IFLTE AP MB P5 MB )) (PLUS MAXPP P15 )
(PLUS(IFLTE P3 P1 MF P14 )(IFLTE TR MF P1
P12 )) (PLUS P11 TL )) Pi photoreceptors TL
turn left TR turn right MF move forward.
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Results photo receptors

• External spreading
• Why ?
• Human eye Diff (Rods)

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Conclusions discussion

• Predator strategy evolvement
• Random strategy
• Left/Right circle rotation strategy
• Combined (Left Right) strategy
• External photoreceptors spared out
• Function redundancy, The key to new life
• None sophisticated strategies
• efficient chase, why ?

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Future work

• More realistic 3D world
• Obstacles
• 3D eye
• 3D world
• Sophisticated preys
• Co-Evolution, prey and predator

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References

• Darwin, Charles On the origin of species by
  means of natural selection. London, John Murray.
  (1859)
• John R. Koza Genetic Programming On the
  programming of computers by natural selection.
  MIT
• Press, Cambridge, Mass. (1992)
• John R. Koza Genetic Programming II Automatic
  Discovery of Reusable Programs. MIT press,
• Cambridge, Mass. (1994)
• John R. Koza Evolution of Subsumption Using
  Genetic Programming. MIT press, Cambridge, Mass.
  (1993)
• Holland, John H. Adaptation in Natural and
  Artificial Systems. Ann Arbor, MI University of
  Michigan Press (1975).
• Haynes, Sen. Evolving behavioral strategies in
  predators and prey, University of Tulsa (1996).

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