Not really, there is no fitness function, there is only some implicit selection pressure. Remember, a single individual is a single password(a string). The program does not keep track of how many viable offspring a parent produces. All an organism does is have sex with other strings in the hope of producing viable offspring(another cracked password). This carries the genetic information on to the next generation while the older generation keeps dying indiscriminatingly, whether they were fit or not since there is no fitness function.