1. The Study of Microevolution Using Agent-Based Modeling
Matt Fifer
Computer Systems Research Project

2. Abstract Agent-Based Agent and Environment classes
Rules for interaction reside in agents
Results predictable but not controllable
Microevolution
Small variations in average characteristics in a community
Process occurs because of inheritability
“Strongest” organisms survive and pass traits on

3. Purpose Controversial issue Creationism vs. Darwinism
Most basic processes debated about
The Experiment
Will attempt to model natural selection at work
If the characteristics have changed, evolution has occurred

4. Background Meiosis Formation of gametes (sperm/egg) Crossing over
Chromosomes, genes, and nucleotides
Natural Selection (a closer look)
Organisms with favorable traits will survive more
More survivors = passing on more genes
Favorable traits become more prominent
“Less fit” organisms gradually reduce in number or perish altogether

5. Procedure Initialization Environment class has matrix of agents
Each cell in matrix either occupied or empty
Organisms equipped with genomes
Simulation
Divided into steps
Organisms interact with neighbors
Can either reproduce, move, kill, die, or stay still

6. Algorithms Agent-Environment
Agent interacts with other agents through environment
Environment collects statistics from matrix
Meiosis
Crossing over
Random assortment
Interaction
Chances of actions depend on genome

7. Results Action probabilities, with mutation Action probabilities,
without mutation

8. Results (continued) Population over time, with mutation
without mutation

9. Conclusions Microevolution
Observe huge increase in tendency to reproduce
Population swings as organisms compete
Start vs. Finish
Beneficial characteristics increase in prevalence
“Super-organisms” thrive; population explosion
Mutation vs. No Mutation
Same trends, both stabilize
Mutation naturally a little more volatile

10. Resources For more information about this topic:
Consult the Advanced Placement Biology textbook
Read Darwin’s The Origin of Species
Talk to an AP Biology student
All of the functions and graphs used in this presentation were written/created by the presenter