The working group "Evolutionary Transitions"


The interdisciplinary working group on "Evolutionary Transitions" was founded on May 6, 2003 at the Center Leo Apostel to study the emergence of multiple levels of complexity, especially in biological, social and computational systems.
 

Theme

The core theme is the analysis and understanding of evolutionary transitions or metasystem transitions, i.e. the fundamental processes through which an emergent system or "layer of reality" arises. Examples include the origin of life, the transition from individual genes to chromosomes, prokaryotes to eukaryotes, unicellular to multicellular organisms, and individuals to societies. Common property of such transitions is that systems which initially were able to survive and reproduce autonomously, consequently have become dependent on a larger synergetic whole.

A number of these wholes can in a later stage again be joined together, forming a supersystem of an even higher order. This produces a "dynamical hierarchy", i.e. a dynamical system exhibiting multiple levels of nested subcomponent structures. The components at each level, their properties, and the modes of interaction between them, all result from the ongoing interactions between the components of lower levels.

Subsequent transitions explain the fundamentally hierarchical evolution of complex systems, and indicate the general trend of increasing complexity, organisation and synergy that characterises evolution.

This subject ties in with:

Short bibliography

Activities

The members of the group include F. Heylighen, T. Lenaerts, C. Gershenson, A. Loengarov, J. Bernheim and G. Van Cronenburg. They will be discussing this subject intensively during the next months, via seminars and a mailing list. A first concrete objective is to prepare papers for the special issue of the journal Artificial Life on "Dynamical Hierarchies" before the Sept. 5 deadline.

The group is associated with the interfaculty Center Leo Apostel (CLEA) of the VUB, but welcomes members from any background or affiliation interested in participating in its (provisionally Brussels-based) activities. All people interested in joining are hereby invited. For more info, contact F. Heylighen.
 

Seminars

You are all invited to come on Tuesdays,  at 17h in the seminar room of the Center Leo Apostel (address below), to participate in our seminars:

May 13: Francis Heylighen:

Aspect co-evolution: a universal mechanism for evolutionary transitions?

Traditional examples of evolutionary transitions are the emergence of multicellular organisms out of single cells, and society out of selfish individuals. The main obstacle to overcome in these are the appearance of "free riders", i.e. individuals that profit from the cooperation between the others but without doing anything in return. Because of their higher individual fitness, free riders will sooner or later outcompete the earnest co-operators, and thus destroy the supersystem from within.

Various explanations have been proposed to explain how cooperation can nevertheless evolve: e.g. kin selection, reciprocal altruism, interiorised morals, market mechanisms, or state institutions. In this seminar I will propose the new abstract mechanism of aspect co-evolution to integrate all these as special cases. The main idea is that the components (cells, individuals, ...) that make up a collective are initially all similar, with similar needs and similar outputs. They thus will be in competition for the same resources, making it difficult to evolve cooperation. Two very different systems, though, can more easily enter into a mutualist relationship where the products of the one may be used as the resources of the other, and vice versa. E.g. a lichen is a symbiotic organism consisting of an alga and a fungus.

A similar complementary relationship can also be attained within a collective, not so much between its components or subsystems, but between functional levels of organization or "aspect systems", that represent different relationships between the same physical components. For example, markets and religions are different "aspect systems" of the same system of society. Being dissimilar and relatively autonomous, while interacting through their shared components, puts the aspect systems in a relation of co-evolution, where they can mutually adapt to reach a symbiotic configuration. This configuration can then act as a control mechanism that suppresses free riders, thus safeguarding the cooperation.



May 27: Tom Lenaerts (Computational Modelling Lab/AI-lab):

Algorithms and Evolutionary Transitions in Complexity.

Evolutionary transitions collect those phenomena in biological evolution where a transition toward more complex entities occurred. Popular examples are the transition from genes to proto-cells (through gene-networks) and from cells to multi-cellular organisms.

The general model which can be derived from these phenomena serves as a collection of guidelines which can be used to design algorithms which produce composite solutions from simple ones.  Yet, it is difficult in that context to build these kind of algorithms.  It is often not clear in many cases how a task can be divided and what the influence is of the different components on each other (interaction). Hence, the most adequate decomposition should be learned automatically instead of being manually constructed. 

Thus from a computer science perspective, instance of evolutionary transitions provide information on how to construct algorithms which are capable of both finding optimal solutions for a particular problem and doing this by hierarchically constructing these solution.  There are different issues which need further investigation since it is often not trivial to translate biological phenomena to usable algorithms.  One of the most important is whether these constuctions are static (or structural) hierarchies or whether they are dynamic hierarchies where a (stable) equilibrium has been reached, within and between levels.

This talk will address the computer science perspective on this issue and discuss some initial steps which have been taken in designing an evolutionary algorithm that, in the long run, is capable of transitions in complexity.



June 3: Geert Vancronenburg (Centrum Statistiek en Operationeel Onderzoek):

System dynamics :  How to obtain insight and make decisions about complex societal issues ?

The goal of this presentation is to give an overview of the state-of-the-art of system dynamics and to explore the possible contributions that system dynamics could make in the future. The following themes will be covered :

1. The history of system dynamics (especially the World3 model, used by the Club of Rome). This component will be important in order to evaluate the implicit goals of system dynamics in the past (‘70s and ‘80s).

2. The search for the social theoretic assumptions underlying system dynamics. For instance, David Lane from the London School of Economics has stated that Giddens’s structuration theory could be a good theoretical foundation of system dynamics. I disagree. I prefer a link with the theoretical research concerning complexity.

3. The difference between the quantitative and the qualitative approach of system dynamics. What are the advantages and disadvantages of both approaches ?

4. The link between uncertainty and system dynamics. Given different kinds of uncertainty, what can our system dynamics models say ? What can they do ?

5. The link between system dynamics and sustainable development.