Biological evolution typically is governed by selectional pressure
at multiple scales and multiple levels. In this talk we report on a number
of studies where we
focus on this aspect of evolution.
First we will discuss that, if coevolution occurs in explicit space,
the evolution of the selfreproducing entities may be enslaved by
the spatial-temporal dynamics to which their interaction gives rise (e.g.
spiral dynamics).
Secondly, diversification at the population level (i.e. 'speciation')
or diversification of the individuals abilities, are two alternative solutions
for coping with spatial/temporal
variation in (coevolving) environmental conditions. We show that
these can be indeed alternative attractors in the same system, and that
the average fitness of the individuals is equal in both cases.
Thirdly we look at differentiation of genes and gene expression patterns
in yeast genomes in the light of the second alternative (individuals coping
with a variety of conditions) and show that a subset of duplicated genes
indeed starts out 'doing the same in different circumstances', i.e. that
regulation differentiation seems to come first.
The fully sequenced genomes show that multicellular organisms differ
mainly from unicellulars in the expansion of intercellular adhesion
- and signalling molecules
Finally we will show some results on the evolutionary dynamics of morphogenesis
governed by differential cell adhesion and intercellular signalling.