What the flu virus is doing isn't so much "evolution" as it is something truly strange since viruses don't have sex.
"What the flu virus is doing isn't so much "evolution" as it is something truly strange since viruses don't have sex."
From the perspective of the virus, it's merely developing immunity to disease.
Evolution doesn't require sex. It requires change in expressed DNA.
sexual reproduction is not a prerequisite to the evolution of a biological system. Virus's mutate (evolve) and the one's that survive and go on to create infectious diseases are the one's that mutate to a form against which a "network" of humans have not developed immunity. That is evolution and survival of the fittest in action.