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Changes in fitness (blue 
) and average adaptiveness (red 
) (ordinate) according to 
(abscissa). For 
, we searched all networks and identified those with high fitness; fitness
for 
, fitness
for 
, and fitness
for 
. While, for 
, the values for the network with the largest fitness at the 
th generation are shown for 
different strains for each 
. 
was set to satisfy 
for 
.
