| Room E6,
Institute of Perception, Action and Behaviour,
Division of Informatics,
University of Edinburgh,
5 Forrest Hill, Edinburgh, EH1 2QL, U.K.
OverviewMy PhD thesis was entitled "From Artificial Evolution to Artificial Life". I am interested in building an artificial environment that is capable of supporting an evolutionary process which is qualitatively similar to the evolution of biological organisms seen in the real world. Some important questions are:-
DescriptionNidus is very different to most existing Artificial Life models of evolution (COSMOS, Tierra etc.). It is a constructive dynamical system, fundamentally similar to that proposed in recent work by Walter Fontana and Leo Buss. It departs from Fontana and Buss' work in that their goal is to build a generalised logical description of chemistry, whereas I wish to implement a system capable of supporting very large populations (of the order of millions of components) capable of evolving living organisations. Nidus therefore has a much more compact (but therefore less general) representation of components, the fundamental interactions are somewhat simpler and require less computation, and it also has an explicit spatial representation. It is similar in may respects to a model of autopoiesis proposed by Francisco Varela et al. and recently resurrected by Barry McMullin, but I have tried to base the Nidus design upon more general and explicit assumptions, and also make it more easily extendable. It is also somewhat related to work by John Holland (the alpha-universes and ECHO), but, again, I have tried to make it more general but at the same time simpler and more computationally efficient. Being a constructive system, the design of individual organisms is not pre-defined, and ecological interactions are modelled more naturally than in Tierra-like systems. Having no pre-defined structure for organisms also leads naturally to the possibility of hierarchical evolution (if the system is composed of the right components and interactions). One way of looking at what I am attempting to do with Nidus is to say that I am trying to embed a Tierra-like population of evolving programs on top of an artificial chemistry.
Current StateJune 1998: The Nidus design is finally complete Implementation will commence in June, followed by a first set of experiments during the summer of 1998. This will be all I have time for before having to write up my PhD. If you'd like to see this system developed further, how about offering me a research post or a job?
DescriptionCOSMOS is an implementation of a Tierra-like system, in which hundreds of computer programs (written in a specially designed language) attempt to copy themselves into new parts of the system's memory, in competition with all the other programs for memory and CPU time. Mutations of various sorts are sometimes introduced into the programs, so that new types of programs appear, the "better" ones survive, and a process of evolution is observed. COSMOS has a few novel features, including:-
Current StateApril 1998: I have finished development work on COSMOS. At present I am performing a series of experiments to test the sensitivity of the system to various parameters, and also to model a number of scenarios that have been proposed to explain the emergence of multicelluler life on Earth. I also plan to develop a simple Java graphical interface for COSMOS in the first half of 1998.