Polyworld is a simulator of artificial life that is to a
large extent constructed according to biological principles.
The organisms in this system develop typical behaviour patterns
and behaviour strategies which are stable on a long-term basis.
Simulations are "successful" if the organisms are
able to reproduce and to maintain their population.
The question is: Are these organisms alive?

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Larry Yaeger

POLYWORLD:
REAL LIFE IN AN ARTIFICIAL CONTEXT?

INTRODUCTION

The subject of this talk will be Artificial Life - the study of man-made living systems. In particular, I will discuss a particular computational ecology, called Polyworld, that represents a seemingly successful attempt to develop nonbiological life in a computer. Though itself nonbiological, PolyWorld draws heavily on biological principles: It brings together biologically motivated genetics, simple simulated physiologies and metabolisms, Hebbian learning in arbitrary neural network architectures, a visual perceptive mechanism, and a suite of primitive behaviors in artificial organisms grounded in a simple ecology. Predation, mimicry, sexual reproduction, and even communication are all supported in a straightforward fashion. The resulting survival strategies, both individual and group, are purely emergent, als are the functionalities embodied in their neural network "brains". PolyWorld is an attempt to approach artificial intelligence the same way that natural intelligence emerged: through the evolution of neural system in a complex ecology.

But are these man-made organisms really alive? Can they be? After presenting some specifics of the pseudo-physics and -biology that constitute PolyWorld's model of life, and showing videotape of some of the species and complex emergent behaviors found in the organisms of PolyWorld, I will try to address this most fundamental question of the field of Artificial Life.

I will conclude with some suggestions for future directions for this research.