Computational Laboratories
and Demonstration Software

Agent-Based Computational Economics (ACE),
Agent-Based Modeling (ABM), and
Complex Adaptive Systems (CAS)

Last Updated: 16 January 2023

Site Maintained By:

Leigh Tesfatsion

Research Professor & Professor Emerita of Economics

Courtesy Research Professor of Electrical & Computer Engineering

Heady Hall 260

Iowa State University

Ames, Iowa 50011-1054

http://www2.econ.iastate.edu/tesfatsi/

tesfatsi AT iastate.edu

ACE Website Homepage

ACE/ABM/CAS General Software and Agent-Based Toolkits

ACE Course 308 (Self-Study eBook)

Site Outline:

• Site Overview
• ACE Comp Labs and Demos
• General ABM/CAS Comp Labs and Demos

Software Release Disclaimer:

All software provided below is unsupported and provided as-is, without warranty of any kind, unless otherwise specified by the provider.

Site Overview

Roughly defined, Agent-based Computational Economics (ACE) is the computational modeling of economic processes (including whole economies) as open-ended dynamic systems of interacting agents. ACE researchers generally conduct their studies in the context of Computational Laboratories (CLs). A CL is a software framework together with a library of software components that permits the plug-and-play development and study of a family of computational models.

To date, however, there does not seem to have been any systematic attempt to encourage the web-publication of these CLs at a centralized accessible site for general ACE research and teaching purposes.

The CLs and demonstration software linked at this site cover ACE applications as well as general Agent-Based Modeling (ABM) and Complex Adaptive Systems (CAS) applications of possible interest to ACE researchers. The ultimate goal of this site is to facilitate the understanding of the ACE methodology by permitting people to obtain hands-on experience running simple ACE/ABM/CAS experiments under different parameter settings with no original programming required and with rapid visual feedback of findings. Not all of the CLs and demos listed below currently possess these desired attributes, but they constitute a useful start towards the goal.

ACE Comp Labs and Demos

• Adaptive Modeler - Agent-Based Financial Market Simulation Platform (Proprietary, Free Evaluation Version)

  The Adaptive Modeler, developed by Jim Witkam (Altreva, Inc.), creates agent-based market simulation models for price forecasting of real world stocks, currencies or other market traded securities. The agent-based model simulates a financial market consisting of thousands of agents whose (technical) trading rules evolve through a special adaptive form of genetic programming. The evolution of trading rules combined with market pricing dynamics drives the agent population to learn to recognize and anticipate recurring price patterns while adapting to changing market behavior. Forecasts can be based on either the behavior of all agents or on a dynamic group of the best performing agents. For ACE researchers this application may be of interest to study the behavior and emergent predictive abilities of an agent-based market model that includes information from a real-world market. Several model initialization options are included such as a user configurable genetic programming engine for the creation of trading rules. Simulation of zero intelligence trading is also supported. Various population statistics and other data can be visualized in charts, distribution histograms and scatter plots, all in real-time. Data can be exported to CSV files for further analysis in other applications. A free (non-expiring) evaluation version with extensive documentation can be downloaded from the Adaptive Modeler homepage, above. Adaptive Modeler is targeted for Windows platforms and requires an installation of Microsoft .Net 2.0 or higher.

  

• Agent-Based Modelling: The BehaviourComposer (U of Oxford, Free)

  The BehaviorComposer is a tool for teaching agent-based modeling (ABM). Not only does it enable students to explore their subjects more deeply through ABM but it also provides them with a first step towards learning computer programming for building models. It is currently being used not only in Biology, but also in business studies and in the study of religion in society. For a short easy guide to the BehaviourComposer visit the Modelling4All YouTube Channel and watch the video tutorial.

  

• AMES Wholesale Power Market Test Bed (Java)

  The AMES Wholesale Power Market Test Bed, developed entirely in Java by an interdisciplinary team of researchers at Iowa State University, is an extensible and modular agent-based computational laboratory for studying the dynamic efficiency and reliability of wholesale power markets restructured in accordance with guidelines issued by the U.S. Federal Energy Regulatory Commission. The framework models strategically-learning traders interacting over time in an ISO-managed wholesale power market operating over an AC transmission grid subject to congestion effects. Congestion on the grid is managed by means of locational marginal prices derived from optimal power flow solutions.

  AMES is a free open-source tool suitable for research, teaching, and training applications. It is designed for the intensive experimental study of small to medium-sized systems. A graphical user interface permits the creation, modification, analysis and storage of scenarios, parameter initialization and editing, specification of behavioral rules (e.g. learning methods) for market participants, and output reports through table and chart displays. AMES is an acronym for Agent-based Modeling of Electricity Systems.

  

• JAMEL: Java Agent-based MacroEconomic Laboratory

  JAMEL (Java Agent-based MacroEconomic Laboratory), developed by Pascal Seppecher (GREQAM), is a cross-platform macroeconomic simulator developed in Java. Applications to date include the study of macroeconomic systems with endogenous money, with productivity shocks, with expenditure shocks, with a flexible labor market, and with a minimum wage. [NOTE: The first time this page is opened, there is a delay due to the loading of a Java applet.]

  

• Keynesian Agent-Based Economic Modelling (Borland Pascal)

  Charlotte Brunn (Aalborg University, Denmark) has developed a software program in object-oriented Pascal (Borland Pascal 7.0) to study the interaction of macro- and microeconomics in a Keynesian world where emphasis is placed on the production circuit rather than on market clearing. Agents, governed by simple decision rules, act on markets for consumption goods, investment goods, labour, and financial assets. The role of credit is given special attention, and the user is, among other things, allowed to turn on or off the credit squeeze. The software program, along with a paper explaining the program, are available for downloading (as zip files) from her home page.

  

• Landscape Dynamics: Evolutionary Games (NetLogo Applets)

  Daniel Friedman and Ralph Abraham (University of California, Santa Cruz) maintain a site titled Landscape Dynamics to showcase some of their efforts to develop a mathematical modeling and computer simulation technology based on evolutionary games with continuous spaces of strategies. Applications to economic systems, such as financial markets, are stressed. NetLogo applets for models developed to date can be found under the "Models" section at this site.

  

• Market Demos (Visual Basic)

  Valentino Piana (Director, Economics Web Institute, Italy) maintains a site devoted to downloadable interactive market simulation models, including "Race to Market," "You are an Exporter," "You are a Monopolist," "The Standard Monopoly Theory," The IS-LM Model" (by Masaru Uzawa), and "Graphical Representations of Cost Functions."

  

• Multi-Agent Economy Simulation (Java)

  Erich Kutschinski and Thoman Uthmann (University of Mainz, Germany) together with Daniel Polani (University of Hertfordshire, UK) have packaged and made publicly available the DMarks II software to accompany their article "Learning Competitive Pricing Strategies by Multi-Agent Reinforcement Learning," Journal of Economic Dynamics and Control, Volume 27 (2003), 2207-2218. Materials provided at this site include the source and compiled code, javadoc, some scripts showing how to run simulations, and a powerpoint presentation. The article is available online at Science Direct.

  

• Santa Fe Artificial Stock Market (Swarm and Objective C)

  The Santa Fe Institute (SFI) has open-sourced the Santa Fe Artificial Stock Market (ASM) simulation model, originally developed by a number of SFI researchers in Objective C using the Swarm toolkit. The latest ASM-Swarm file releases can be downloaded from an ASM sourceforge page and repository maintained by Paul E. Johnson (Political Science, University of Kansas, Lawrence).

  

• Small-World Trade Network Demo (NetLogo)

  The Small-World Trade Network Demo developed by Mark McBride (Professor of Economics, Miami University, Oxford, Ohio) implements a trade model designed by Allen Wilhite (Computational Economics, 2001). The purpose of the Wilhite trade model is to examine the effects of small-world network structure on the market efficiency of bilateral trade. The Small-World Trade Network Demo can be either be run in a web browser or downloaded as a NetLogo file to run locally using NetLogo 4.0.3 (or higher). Possible network structures available for testing include globally (completely) connected, locally connected, locally disconnected, and small-world (local connectivity with global reach). See, also, Notes on the Wilhite Trade Model.

  

• Sugarscape (Object Pascal, NetLogo, MASON)

  Joshua Epstein and Rob Axtell have developed an agent-based computational framework, Sugarscape, for the study of human social phenomena such as trade, migration, group formation, combat, interaction with an environment, transmission of culture, propagation of disease, and population dynamics. See J. Epstein and R. Axtell, Growing Artificial Societies: Social Science from the Bottom Up, MIT Press/Brookings, MA, 1996.

  • A brief review (ps,28K) of the Epstein-Axtell monograph by L. Tesfatsion appears in "Review of J. M. Epstein and R. Axtell, Growing Artificial Societies: Social Science from the Bottom Up," Journal of Economic Literature XXXVI (March 1998), pp. 233-234.
  • A CD-ROM edition of the monograph is available; for ordering information, contact the Brookings Institution Press.
  • The CD-ROM edition operates on both Macintosh and Windows platforms and contains the complete text as well as the Sugarscape animations, which can be viewed in their entirety.
  • The original Object Pascal source code for Sugarscape is not publicly posted (interested readers should contact the authors for availability information).

  Tony Bigbee has released a Java-based open source replication of the classic Sugarscape model, called MASON Sugarscape, that is implemented using George Mason University's MASON agent-based simulation toolkit. Most, but not all, of the Sugarscape rules are implemented.

  

• TNG Lab: A Computational Laboratory for Evolutionary Trade Networks (WinDesktop, C++/Visual Basic)

  The Trade Network Game Laboratory (TNG Lab) is a computational laboratory for exploring the evolution of trade networks among strategically interacting traders (buyers, sellers, and dealers) operating under variously specified market protocols. The TNG Lab blends and extends standard matching theory and sequential game theory in that each trader jointly determines over time both whom to seek trades with (partner selection) and how to behave in any trade interactions that take place (strategy selection).

  Once a trade partnership is determined, the partners engage in a bilateral trade interaction modeled as a symmetric 2-person game (e.g., Prisoner's Dilemma, Chicken, Stag Hunt). The traders use genetic algorithm learning to evolve their trading strategies over time based on outcomes from their past trade interactions. The TNG Lab has a clear easily-operated Graphical User Interface (GUI) that permits users to experiment with alternative settings for key parameters pertaining to learning, payoffs, types and numbers of agents, and the physics controlling network displays. The formation/evolution of trade networks is visualized by means of run-time animations, run-time charts, and run-time data displays.

  Automatic installation software for the TNG Lab, together with tutorials and research articles, can be obtained at the TNG Home Page.

  

• Winner's Curse Applet

  Mike Shor (Owen Graduate School of Management, Vanderbilt University) has developed a Winner's Curse Applet that permits users to experimentally explore the well-known "winner's curse" problem in common-value auctions. The Winner's Curse is the observation that winners in such auctions typically turn out to pay too much relative to true valuation. They win because they are overly optimistic.

  

• Zero-Intelligence Trading Demo (Java Applet/NegLogo Model)

  Mark McBride (Economics Department, Miami University, Ohio) has developed Zero-Intelligence Trading Demonstration Software that is based upon the double-auction trading experiments conducted with "Zero-Intelligence (ZI)" traders by Gode and Sunder (Journal of Political Economy, 1993). A Java Applet is available at this site that permits you to run ZI trading experiments in a Java-enabled browser (Java 1.4.X or later). Alternatively, a NetLogo model can be downloaded for running on a personal computer with a NetLogo 3.1.1 (or later) installation.

General ABM/CAS Comp Labs and Demos

• Artificial Life Resource Site: Zooland

  From 1995-2004 Jörg Heitkötter maintained an extensive, annotated, and carefully categorized site titled Artificial Life Resource Site: Zooland that includes demos for many of the most famous early alife models.

  

• Artificial Life (Java Applets)

  Tim Tyler provides collections of interactive Java applet demonstrations focusing on artificial life and texture generation at a Web site titled Lotus Artificial Life

  

• Axelrod Tournament Demo (WinDesktop, C#/.Net)

  In 1979, Robert Axelrod (University of Michigan, Ann Arbor) posed an intriguing question: What type of strategy (if any) ensures good individual performance over the long haul when one is engaging in repeated Prisoner's Dilemma game play in round-robin fashion with multiple strangers whose strategies are not known in advance? Axelrod explored this question by conducting a computer tournament with strategies solicited from game experts from all over the world.

  Chris Cook (Computer Science Department, Iowa State University, Ames) has developed the Axelrod Tournament Demo, a computational laboratory that captures and extends the salient aspects of Axelrod's 1979 tournament. The Axelrod Tournament permits a user to specify as treatment factors the number of tournament iterations, the total number of agents (strategies) comprising the initial tournament population, the types of agents in this population, and the form of payoff matrix for each agent type. The latter feature extends Axelrod's original tournament by permitting matched agents to engage in a wide variety of two-player games (Chicken, Stag Hunt, etc.) depending on their specified types. The user can then observe the comparative performance over time of each agent, and each agent type, by means of run-time graphical and text displays.

  Cook's Axelrod Tournament Demo is available as freeware under the GNU Public License. Automatic installation software for this computational laboratory, together with more detailed information about its capabilities and implementation, can be obtained at The Axelrod Tournament: Demonstration Software (html).

  

• Biomorphs: Simulation of Biological Evolution

  In The Blind WatchMaker (W.W. Norton and Co., New York, 1987), Richard Dawkins introduces the concept of "biomorphs," i.e., encapsulated software programs capable of breeding. Those bred within a particular "pedigree" have a precisely known relationship to each other and a precisely known genetic make-up. Dawkins (Appendix, p. 15) claims that these features make biomorphs "ideally suited to verifying methods of taxonomy, and also to teaching the principles of taxonomy."

  A large variety of interactive biomorph demos are available on-line. For a simple example, see the demo at Richard Dawkins' Biomorphs. An interactive biomorph demo with interesting additional features can be found at Introduction to Biomorphs.

  

• Boids: Simulation of Flocking Creatures (Java Applets)

  Craig Reynolds (Sony, Research and Development Group) maintains a web site titled Boids featuring his simulations of flocking creatures called "boids." His basic flocking model consists of three simple steering behaviors possessed by each individual boid that govern how each boid maneuvers itself based on the positions and velocities of its nearby flockmates. As illustrated by the Java applets at this site, the model results in amazingly life-like collective flocking dynamics. Also available at this site is a link to work by Reynolds on an interactive system permitting user interaction with large groups of autonomous characters. The characters respond in real time to the user's interaction as well as to each other and their environment.

  

• Cellular Automata Lab (WinDesktop)

  From the CelLab User Guide: "The first edition of CelLab was developed by Rudy Rucker and John Walker in 1988 and 1989 when both were working in the Autodesk research lab... Celab allows you to explore cellular automata on your own personal computer, running under MS-DOS or Windows. You can define your own rules by writing short programs in Java, C, BASIC, or Pascal, create patterns of cells and color palettes, then run the rule and observe its evolution on the screen. We supply a wide variety of ready-to-run rules, simulating processes as varied as heat flow, diffusion of gases, annealing of metal, behavior of tubeworms on the ocean floor, chemical reactions, and ecosystems of artificial life. Complete source code for all of these rule definitions in included in both Java and Pascal, allowing you to use our rule definitions as the point of departure for your own experiments. Advanced users can customize the cellular automata simulator by writing custom evaluators in assembly language for DOS or Windows, or as a DLL written in C for the Windows-based simulator."

  Rudy Rucker is Professor of Mathematics and Computer Science at San Jose State University. John Walker is founder and former president of Autodesk, Inc.

  

• Cellular Automata: Mirek's Cellebration (Windows)

  Mirek's Cellebration (MCell) is a freeware computer program for running one-dimensional and two-dimensional cellular automata. It is written by Mirek Wójtowicz and runs on a Windows platform. It has support for many rules in fifteen different families: "Life", "Generations", "Weighted Life", "Vote for Life", "Rules tables", "Cyclic CA", "1-D binary CA", "1-D totalistic CA", "Neumenn binary", "General binary", "Large than Life", "Margolus neighborhood", "User DLLs", "Special rules", and "Weighted Generations". The latest versions allow users to rewind to previous generations of any open cellular automata, undo changes made to the grid, and find periodic patterns automatically. Extensive CA materials, downloadable source code, and code documentation are available at the above MCell site.

  

• Complex Adaptive Systems Demos (Mac)

  Robert Goldstone (Department of Psychology, Indiana University) maintains a site that provides Complex Adaptive Systems Demonstration Software for an undergraduate course he teaches on complex adaptive systems. The software programs available at this site, designed to be run on Macintosh computers, permit students to explore complex systems interactively by setting experimental parameters, conducting experiments, and instantly seeing the results of the experiments.

  

• Complexity Class Materials

  Scotte Page (Complex Systems, Political Science, and Economics, U of Michigan) has posted Complexity Class Materials for an undergraduate course on complexity modeling and game theory.

  

• Complexity Workshop (Tutorials/Demos)

  Owen Densmore has developed a Repast Tutorial and a NetLogo Tutorial aimed at researchers and business people who are computer and complexity novices. These tutorials use two generally available modeling systems, Repast and NetLogo. Both tutorials begin with how to download and install the software and access the documentation and "demo" models. They both then lead the reader through building a very simple model of the buttons phase transition presented in Stuart Kauffman's book At Home in the Universe. Repast and NetLogo are chosen for their synergy: a project will typically explore several potential models using NetLogo as a "what-if" environment, then graduate to RePast for its performance and access to more advanced features such as Geographical Information Systems. The initial NetLogo simulations provide additional value by being easily put into web pages as applets.

  

• Emergence: Interactive Tutorial

  Mitchel Resnick and Brian Silverman (Epistemology and Learning Group, MIT Media Laboratory) have developed an interactive tutorial on Emergence. The authors examine how objects and patterns can arise from simple interactions in ways that are surprising and counterintuitive.

  Note: A Java-enabled browser is required to run the applets accompanying this tutorial.

  

• Evolution of Cooperation and the Prisoner's Dilemma

  The Complexity of Cooperation Website provides software and documentation (as well as other resources) related to two books by Robert Axelrod: (a) The Complexity of Cooperation: Agent-Based Models of Competition and Collaboration, Princeton University Press, 1997; and (b) The Evolution of Cooperation, Basic Books, 1994.

  

• Game of Life (Java Applet)

  Paul Callahan maintains a site called What is the Game of Life?. This site explains and presents, in interactive form, a delightful game invented by John Conway in the 1970s demonstrating that even very simple rules can lead to extremely complicated outcomes.

  

• Game of Life (WinDesktop)

  Johan Bontes (University of Wisconsin) maintains a site titled Life32 where people can go to download and install Game of Life freeware for Windows Win9x/NT/2000/XP. Bontes describes Life32 as the "best, fastest, most user-friendly life player around."

  

• Hunter-Gatherer Artificial Society (WinDesktop, C#/.Net)

  Andrew Schlei (Computer Science Department, Iowa State University, Ames) has developed an interactive demo of a spatial hunter-gatherer society, called Hunters. The Hunters demo, targeted for the Microsoft desktop, has an easily manipulated graphical user interface. A population of hunter-gatherer agents, called hunters, must secure food in order to survive. Food can be gathered at food sources randomly located throughout the hunters two-dimensional cellular world. The Hunter agents have three possible food strategies: (1) Gather food and hoard it for later consumption; (2) attack and steal food from other agents they encounter; or (3) share food with other agents they encounter. The behavior of Hunter agents is governed by two factors: individual learning; and evolution of the population in accordance with natural selection principles.

  Andrew Schlei has released his Hunters demo as freeware under the GNU Public License. Automatic installation software for his Hunters demo can be obtained at The Hunters Home Page. Also available at this site is a more detailed description of the Hunters world, a description of the Hunter demo's capabilities, instructions for using the automatic installation software, a link for accessing the Hunters demo source code (Visual C++), and copyright information.

  

• Mandelbrot and Julia Sets (On-Line)

  David Joyce (Department of Mathematics and Computer Science, Clark University, Worcester, MA) maintains an interactive website where interested parties can create and view images of Mandelbrot and Julia Sets. The website also includes an archive of recently created images as well as pointers to related websites.

  

• Mophological Simulations: Karl Sim's Interactive Works (On-Line)

  Karl Sims (GenArts, Inc., Cambridge, Massachusetts) has created a variety of interactive computer displays involving the evolution of 3D animated forms. For more information, visit Karl Sims' Home Page.

  

• NetLogo Agent-Based Modeling: The Modelling4All Project (On-Line)

  The Modelling4All Project at the University of Oxford has built the Behaviour Composer, a web-based application for building and running NetLogo agent-based models. NetLogo models are broken down into "micro-behaviours". Each micro-behaviour lives on its own web page. The Behaviour Composer can be used from any browser. In it one browses for micro-behaviours, assembles them into prototypes (similar to NetLogo breeds), and the service generates a complete NetLogo program that can be run as an applet or downloaded into NetLogo. To facilitate the modularity of micro-behaviours we have added to NetLogo scheduling primitives and support for simultaneous updates. The software has been especially successful in a classroom setting where students are able to assemble, run, experiment with, and analyse serious models without first learning NetLogo programming. The site and web-based tools are free to all. The source code is open.

  

• NetLogo Models

  The Center for Connected Learning (Northwestern University, Evanston, Illinois) maintains a NetLogo User Community Models Site that provides links to models contributed from the NetLogo user community to be shared with other NetLogo users. The models cover a wide range of topics in biology, chemistry, physics, and the social sciences. For example, the social science models include a simple version of the Schelling Segregation Model and various prisoner's dilemma models.

  

• Newton Basins (On-Line)

  Nonlinear equations F(x)=0 typically have multiple solutions x. Newton's method for finding solutions to nonlinear equations is a successive approximation technique with the property that different starting points can converge to different solutions. A Newton basin is a set of starting points for Newton's method that all lead to one particular solution. It turns out that Newton basins are "fractals" in the complex plane with beautifully intricate boundaries that can be visualized by applying distinct colorations to starting points converging to distinct solutions (or to no solution). David Joyce (Department of Mathematics and Computer Science, Clark University, Worcester, MA) maintains an interactive website where interested parties can create and view images of Newton Basins.

  

• Political Simulation (Win or Mac Excel)

  Political Sim was created to make the power of voting rules easy to understand through visual displays. Political Sim lets players experiment with forty-one flavors of democratic voting, from Australia to Zuidland. Political Sim can be downloaded in self-extracting compressed files for use with Windows Excel or Macintosh Excel. For more information, visit here.

  

• Predator-Prey and Social Game Simulations (Java Applet)

  William F. Harms (Seattle, Washington) has developed an interactive predator-prey ecological simulation (Java applet). He has also developed interactive simulations for several of the dynamic games described in Brian Skyrms' book Evolution of the Social Contract (Cambridge University Press, 1996). The latter games include: divide the cake; the ultimatum game; correlated equilibria games; and signalling games. For more information, visit here.

  

• Prisoner's Dilemma Game (On-Line)

  The University of Toronto maintains an Interactive Tutorial on the Prisoner's Dilemma Game.

  

• Sand Pile Model (Applet)

  Sergei Maslov (Biology Department, Brookhaven National Laboratory, Long Island, NY) has developed an applet implementing the Bak-Tang-Wiesenfeld (BTW) Sandpile Model.

  

• Schelling Segregation Model (WinDesktop, C#/.Net)

  Chris Cook (Computer Science Department, Iowa State University, Ames) has developed an interactive demo of the Schelling Segregation Model (SSM), due to Thomas Schelling (Micromotives and Macrobehavior, Norton, 1978). The SSM demo, targeted for the Microsoft desktop, has an easily manipulated graphical user interface. Agents are located on a chess board with 64 locations. The user determines the population mix from among three agent types (red, green, and blue), or chooses from among various default settings. The user can also specify a "happiness rule" for each agent type or select a default setting. The happiness rule determines when an agent is happy with his current board location, taking into account both the number and the types of his neighbors. If unhappy, the agent either attempts to move to a more desirable board location or exits the board altogether.

  Chris Cook has released his SSM demo as freeware under the GNU Public License. Automatic installation software for his SSM demo can be obtained at The Schelling Segregation Model: Demonstration Software Also available at this site is a more detailed description of the SSM, a description of the SSM demo's capabilities, instructions for using the automatic installation software, a link for accessing the SSM demo source code (C#/.Net), and copyright information.

  

• Schelling Segregation Model (Repast)

  Lars-Eric Cederman (ETH) maintains a Schelling Segregation Model Demo (Repast). Materials available at this site include documentation and software downloads.

  

• Segregation Simulators (WinDesktop and Java Applet)

  Mark Fossett (Department of Sociology, Texas A&M University) has developed VLAB-RESI, an interactive software program simulating the dynamics of residential segregation by ethnic and socioeconomic status. Program files and documentation files for downloading, installing, and running VLAB-RESI are available at this site. Fossett has also developed two more limited Java applet versions of his software program called SimSeg Lite I and SimSeg Lite II, also available at this site, that can be run on-line via a java-enabled browser.

  

• Tierra (C Source Code)

  Tierra is a digital universe developed by Tom Ray (University of Oklahoma, Norman, OK) in which self-replicating machine code programs evolve by natural selection in an open-ended arms race between hosts and parasites. A general description of Tierra, together with detailed instructions for downloading and running the Tierra source code, can be obtained at the Tierra Home Page.

Copyright © Leigh Tesfatsion. All Rights Reserved.