# Polyworld

> Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Polyworld
> Markdown URL: https://mediated.wiki/source/Polyworld.md
> Source: https://en.wikipedia.org/wiki/Polyworld
> Source revision: 1341365646
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

{{Short description|AI life simulation using evolutionary algorithms}}
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| caption = Polyworld Screenshot, 1994
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'''Polyworld''' is a cross-platform ([Linux](/source/Linux), [Mac OS X](/source/Mac_OS_X)) program written by [Larry Yaeger](/source/Larry_Yaeger) to evolve [Artificial Intelligence](/source/Artificial_Intelligence) through [natural selection](/source/natural_selection) and [evolutionary algorithm](/source/evolutionary_algorithm)s. 

It uses the [Qt](/source/Qt_(toolkit)) graphics toolkit and [OpenGL](/source/OpenGL) to display a graphical environment in which a population of trapezoid agents search for food, mate, have offspring, and prey on each other. The population is typically only in the hundreds, as each individual is rather complex and the environment consumes considerable computer resources. The graphical environment is necessary since the individuals actually move around the 2-D [plane](/source/Plane_(mathematics)) and must be able to "see." Since some basic abilities, like eating carcasses or randomly generated food, seeing other individuals, mating or fighting with them, etc., are possible, a number of interesting behaviours have been observed to spontaneously arise after prolonged evolution, such as cannibalism, predators and prey, and mimicry.

Each individual makes decisions based on a [neural net](/source/neural_net) using [Hebbian learning](/source/Hebbian_learning); the neural net is derived from each individual's genome. The genome does not merely specify the wiring of the neural nets, but also determines their size, speed, color, [mutation rate](/source/mutation_rate) and a number of other factors. The [genome](/source/genome) is randomly mutated at a set probability, which are also changed in descendant organisms.<ref>{{Cite web |last=Yaeger |first=Larry |title=Yeager: Computational Genetics, Physiology, Metabolism, Neural Systems, Learning, Vision, and Behavior |url=https://shinyverse.org/larryy/Yaeger.ALife3.pdf |access-date=July 26, 2024 |website=}}</ref>

==References==
{{reflist}}

==External links==
*[https://github.com/polyworld/polyworld Github entry]
*[https://shinyverse.org/larryy/Polyworld.html Yaeger's page on Polyworld]
*[https://www.youtube.com/watch?v=_m97_kL4ox0 Google TechTalk about Polyworld]

Category:Applications of artificial intelligence
Category:Artificial life
Category:Digital organisms

{{science-software-stub}}

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Adapted from the Wikipedia article [Polyworld](https://en.wikipedia.org/wiki/Polyworld) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Polyworld?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.