Serendip is an independent site partnering with faculty at multiple colleges and universities around the world. Happy exploring!

Emergence 2009: Semester Projects I

Emergence

Biology 361 = Computer Science 361
Bryn Mawr College, Spring 2009

 

Back to index of models

 

 

Download/view: Evolve04.nlogo

 

WHAT IS IT?
This model is a preliminary stage in my effort to create a basic model of evolution.
HOW TO USE IT
SETUP, STEP, and GO are standard.

ADD PREDATOR adds a single predator at a random location.

INIT-PREDATORS controls how many predators are included in SETUP.

PRED-RADIUS controls the radius in which predators can sense prey.

INIT-PREY controls how many prey are included in SETUP.

SPAWN-AGE controls how many ticks prey must survive for before reproducing.

TRAIT-SETUP controls how the distribution of sight-dist values within the prey population upon SETUP. RANDOM sets each to a random value from 0 to 9, NORMAL sets them randomly based on a normal distribution. SET TO SLIDER sets the value for all turtles to the value set by the INIT-SIGHT-DIST slider.
THINGS TO NOTICE
I used separate breeds for predators and prey so that I could easily control them separately.  I also had to do some careful thinking to get the graph working how I wanted- note the recursion and 'bins' in the graph-trait procedure and the use of the ROUND primitive.
THINGS TO TRY
Try starting out with no predators. Use different TRAIT-SETUP options and different slider settings for the SET TO SLIDER option. Watch how the mean and distribution of trait values varies. Next try adding a predator (or doing a SETUP with some INIT-PREDATORS)- how do predators affect the mean and distribution of trait values? Can you select settings that cause all the prey to go extinct?
EXTENDING THE MODEL
I am intending to incorporate more traits for the prey, starting with limiting their sight to a specific field of vision.  I would also like to add some traits for the predators and see what kind of 'arms race' results.

 

Models created using NetLogo.

Comments

Post new comment

The content of this field is kept private and will not be shown publicly.
To prevent automated spam submissions leave this field empty.
3 + 0 =
Solve this simple math problem and enter the result. E.g. for 1+3, enter 4.