Dude, where is my sex gene? — Persistence of sex over evolutionary time in cellular automata

We created a simple evolutionary system, F-sexyloop, on a deterministic twelve-state five-neighbour cellular automaton (CA) where self-reproducing loops have the capability of sex. This work was based on the sexyloop which was transformed by adding two new states and new rules. In the F-sexyloop, the loops can carry a sex gene used to facilitate the transfer of genetic material from a loop to another. This gene is analogous to the F factor plasmid in bacterial conjugation which confers the capacity to act as a donor of genetic material (including the gene itself). Therefore, the sex gene could potentially be maintained in the population during evolution or disappear. We show that in a wide variety of cases, the sex gene persists over evolutionary time and is present in the genomes of the dominant species.