through 3 simple rules, resul0ng in flocking behavior • Emergence – complex behavior arises from simple rules • Eventual basis for some impressive cinema anima0on – Lord of the Rings, Batman Returns, Lion King etc
other and the environment • Used in analysing supply chain op0miza0on, traffic paSerns, economic models, spread of epidemics • Influenced by John Conway’s Game of Life • Heavily influenced by Epstein and Axtell’s Sugarscape simula0ons
an energy level (randomly assigned, max 100) • At every 0ck, roids lose 1 energy • If energy level reaches 0, it will die • To prevent this, it will ac0vely seek out food and consume it • Consuming food replenishes energy level • (But roids are s0ll immortal)
is a measure of the inequality of a distribu0on, 0 is perfect equality and 1 is perfect inequality • Defined mathema0cally based on the Lorenz curve Area is the amount of inequality
• Back to where we started – emergence • Small changes ripple down to large effects over a period of 0me • Simple local rules brings complex global changes
now – male and female • Males are blue, females are red, underaged are • If female is within childbearing age (25 to 50 0cks) and if it has enough energy, it will look for a nearby male • If the male it encounters is also within childbearing age and have enough energy, they will procreate and produce a baby roid • Both male and female loses energy each 0me they procreate
• Each roid has a randomly assigned lifespan • Each 0ck increases the age of the roid • Roid dies when it reaches its lifespan (no maSer how much energy it has)
popula0on changes once we introduce sex and death • At every 0ck we collect the popula0on of the en0re world, as well as popula0on of males and females
animal ex0nc0ons, climate change? • Simula0on suggests small internal factors can be enough to trigger crises that cannot be recovered • Not necessarily need large external triggers
• “Survival of the fiSest” • Organisms with more suitable aSributes are more likely to reproduce and pass these aSributes to the next genera0on • Over 0me these aSributes become more prominent
the same aSributes, only difference is maximum lifespan and energy level • In this simula0on, we add 2 new aSributes – Metabolism How well the roid converts the food it eats into energy (higher number beSer) – Vision range How far away it can see food (higher number beSer) • Roid babies inherit these 2 aSributes from their parents
Mendelian rules for crossover • Assume the father has the genotype (m,v) and the mother has genotype (M,V) • Possible genotypes of baby are (m,v), (m,V), (M,v) and (M,V) • We randomly chose 1 of these 4 possibili0es
the metabolism and vision range aSributes of the popula0on changes over 0me • At every 0ck, we calculate the average metabolism and vision range of all roids that are alive
the roids with the beSer aSributes are able to survive longer and reproduce with similar aSributes • Natural selec0on is not necessarily a straight line (vision range meanders for a while)
a roid dies of old age, his collected energy dissipates • What happens if the collected energy of a roid is passed on to his children instead? • This simulates wealth gathered by the parents being inherited by the children
simula0on except that when a roid dies, the energy he collects over his life0me is distributed to his children • Compare the evolu0on simula0on with the inheritance simula0on
to isolate factors for inves0ga0on • Conclusions open for interpreta0on (Lies, damn lies and simula0ons) • Programming as tools to discover the world around us