Evolving Digital Ecological Networks

<div><p>“<i>It is hard to realize that the living world as we know it is just one among many possibilities</i>” <a href="http://www.ploscompbiol.org/article/info:doi/10.1371/journal.pcbi.1002928#pcbi.1002928-Jacob1" target="_blank">[1]</a>. <b>Evolving digital ecological networks</b> are webs of interacting, <a href="http://en.wikipedia.org/w/index.php?title=self-replication" target="_blank">self-replicating</a>, and <a href="http://en.wikipedia.org/w/index.php?title=evolution" target="_blank">evolving</a> <a href="http://en.wikipedia.org/w/index.php?title=computer_program" target="_blank">computer programs</a> (i.e., <a href="http://en.wikipedia.org/w/index.php?title=digital_organism" target="_blank">digital organisms</a>) that experience the same major <a href="http://en.wikipedia.org/w/index.php?title=ecology" target="_blank">ecological interactions</a> as <a href="http://en.wikipedia.org/w/index.php?title=biological_organism" target="_blank">biological organisms</a> (e.g., <a href="http://en.wikipedia.org/w/index.php?title=Competition_(biology)" target="_blank">competition</a>, <a href="http://en.wikipedia.org/w/index.php?title=predation" target="_blank">predation</a>, <a href="http://en.wikipedia.org/w/index.php?title=parasitism" target="_blank">parasitism</a>, and <a href="http://en.wikipedia.org/w/index.php?title=Mutualism_(biology)" target="_blank">mutualism</a>). Despite being computational, these programs evolve quickly in an open-ended way, and starting from only one or two ancestral organisms, the formation of ecological <a href="http://en.wikipedia.org/w/index.php?title=Biological_network" target="_blank">networks</a> can be observed in real-time by tracking interactions between the constantly evolving organism <a href="http://en.wikipedia.org/w/index.php?title=phenotype" target="_blank">phenotypes</a>. These phenotypes may be defined by combinations of <a href="http://en.wikipedia.org/w/index.php?title=Boolean_logic" target="_blank">logical computations</a> (hereafter tasks) that digital organisms perform and by expressed <a href="http://en.wikipedia.org/w/index.php?title=behavior_(biology)" target="_blank">behaviors</a> that have evolved. The types and outcomes of interactions between phenotypes are determined by task overlap for logic-defined phenotypes and by responses to encounters in the case of behavioral phenotypes. Biologists use these evolving networks to study active and fundamental topics within <a href="http://en.wikipedia.org/w/index.php?title=Evolutionary_ecology" target="_blank">evolutionary ecology</a> (e.g., the extent to which the architecture of multispecies networks shape coevolutionary outcomes, and the processes involved).</p>