Digital organism
Digital organisms are parts of computer programs that can be reproduced independently , modified and thus changed in their behavior. They use principles that come from evolutionary theory and genetics .
history
Digital organisms can be traced back to the game Darwin, which was developed at Bell Laboratories in 1961 . Computer programs competed with each other by trying to stop each other from running on the computer. A subsequent and similar implementation was the game Core War . In Core War, the best strategy was to multiply as quickly as possible and thereby deprive your opponents of system resources . Computer programs within Core War could change themselves as well as opponents by overwriting code in the memory area in which the game was simulated. This allowed the computer programs to incorporate malicious instructions in the opponent that caused errors (terminated the process) or to reprogram the opponent to work for the program that was manipulating him.
Steen Rasmussen at Los Alamos National Laboratory took the idea of Core War and developed it further in his Core World System by introducing a genetic algorithm that automatically wrote computer programs. However, Rasmussen could not observe any evolution of complex and stable computer programs. It turned out that the programming language in which the computer programs in Core World were written was not stable enough and that the mutations often led to the functionality of a program being completely destroyed.
The first person to solve the stability problem was Thomas S. Ray with his Tierra program . Ray made significant changes to the programming language, such as making it less likely that mutations would destroy an entire program. These changes made it possible for the first time for computer programs to evolve in a complex and meaningful way.
In 1993, Christoph Adami, C. Titus Brown and Charles Ofria began developing the Avida system, which was inspired by Tierra, but again showed significant changes. In Tierra, all programs are in the same address space , which means that computer programs can overwrite each other or interact in other ways. In Avida, however, each computer program lives in its own address space. Thanks to this change, experiments with Avida are much cleaner and easier to interpret than those with Tierra. With Avida, research with digital organisms began to be viewed by a growing number of evolutionary biologists as a legitimate contribution to evolutionary biology . Evolutionary biologist Richard Lenski of Michigan State University has Avida used extensively for his research. Lenski, Adami and others of their colleagues have published their results in scientific journals such as Nature and the Proceedings of the National Academy of Science (USA) .
literature
- Eberhard Schöneburg, Frank Heinzmann, Sven Feddersen: Genetic Algorithms and Evolution Strategies: An Introduction to Theory and Practice of Simulated Evolution . 1st edition. Addison-Wesley, Bonn; Paris; Reading, Mass. [u. a.] 1994, ISBN 3-89319-493-2 .
Individual evidence
- ↑ McIlroy, MD, Morris, R., Vyssotsky, VA (1971). "Darwin, a Game of Survival of the Fittest among Programs"
- ^ Aleph-Null, "Computer Recreations," Software: Practice and Experience, vol. 2, pp. 93–96, 1972 PDF ( Memento of the original from July 14, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. HTML ( Memento of the original from November 29, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Dewdney, AK (1984). In a game called core, hostile programs engage in a battle of bits. Scientific American , 250 (4), 14-22 HTML
- ↑ Rasmussen, S., Knudsen, C., Feldberg, R., & Hindsholm, M. (1990). The coreworld — Emergence and evolution of cooperative structures in a computational chemistry. Physica D, 75, 1-3
- ↑ Ofria C. and Wilke CO (2004) Avida: A Software Platform for Research in Computational Evolutionary Biology, Journal of Artificial Life ( Memento of the original from June 3, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked . Please check the original and archive link according to the instructions and then remove this notice. , 10: 191-229.
- ↑ http://avida.devosoft.org/
- ^ Lenski RE, Ofria C., Pennock RT, and Adami C. (2003) The Evolutionary Origin of Complex Features, Nature , 423: 139-144
