They mutate due to RNA being unstable. It has high probability of mutations. Those mutations happen with every virus and natural selection selects for the weaker viruses because the sicker you are, the less likely you're going to go out and spread it. This leaves the weaker viruses to spread.
That's not how viruses work.
They mutate due to RNA being unstable. It has high probability of mutations. Those mutations happen with every virus and natural selection selects for the weaker viruses because the sicker you are, the less likely you're going to go out and spread it. This leaves the weaker viruses to spread.