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local maxima of the function. The agents store in their genotype the information
about their location in the area of the function's domain, the value of which is used
for demarcating the level of adaptation of this agent. The genotype of the agent
which is processed within the evolution operations contains the information about
characteristic features of the agent and about its location in the domain of the function
f R . In these examples, the agents acting in the system are governed by typical evolution
operations such as cloning, crossing over and mutation. Moreover, operations typical
of the co-evolution systems such as operations of migration (relocation between the
vertices of a graph), operations related to inter-sexual interactions as well as the
operations of aggregation (creation of aggregates in the form of niches) were used.
The systems used in experiments have the following properties:
ACoEMAS System is the co-evolution agent system with the speciation mech-
anism based on the geographic isolation of the subpopulation (referred to as the
allopatric speciation), which constitutes the mechanism leading to the origin of
species. To this purpose, barriers are created which make it difficult for agents to
migrate between the vertices of the graph (i.e. environment). The agent, to get from
one vertex to the other, uses a large amount of energy (“life energy”) which is the
said barrier. It gives the possibility of mutual isolation of the group of agents and
makes the origin of species easier.
SCoEMAS System is the co-evolution agent system, using the concept of sex, with
both sexes within each species. Interactions between the subjects of both sexes are
made possible in the system, particularly each agent for the realization of the oper-
ation needs to find (and accept) the subject of the opposite sex. Generally speaking,
the interactions in the form of conflict and co-evolution of sex, sexual selection as
well as matching agents in pairs for a longer time are used here which is possible
due to the operation of aggregation. Aggregation is a situation when two agents of
the opposite sex which are “ready for” crossing make a pair (aggregate) which lasts
for some time. The pair may relocate in the environment and realize the operation of
crossing several times. Apart from these interactions in the SCoEMAS system, there
are other interactions between species such as rivalry for resources (existing in the
environment in limited number).
NCoEMAS System is the co-evolution system using the concept of niche for the
creation of species (suggested in the paper [77]). In that solution, the agents creating
the populations of subjects may use the aggregation operation to create niches that
constitute a certain local environment for the agents. There are agents and niches in
the environment. The environment of agents and niches is the domain of the function
f R and the location of the agent specified by its positions in this domain. Niches
are represented by a special “agent of the niche” that identifies a given niche in the
agent system. The location of the niche is defined as the location of the agent of
the niche, and this is specified as the location of the centre of gravity of the agents
which belong to a given niche (where “the weight of the agent” is specified by the
value of its adaptation function, i.e., the value of the function f R ). The introduction
of the agent of the niche allows for the realization of certain evolution operations at
the niche level, which gives the possibility of realizing evolution processes at two
levels: at the level of subjects, and at the level of niches. The location of one agent in
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