Post by r***@gmail.comPost by Loren PechtelLocal stuff isn't going to mutate that fast.
I do agree benign stuff could possibly turn hostile but that's
unlikely--there's no drive to be hostile. The evolutionary pressure
on pathogens is to be benign. The deadly stuff is generally fairly
recent species jumps.
How many times have you had a cold, or caught the flu?
When I attended university, there were enough students from elsewhere
cycling in every semester that there was a new set of cold viri every
four months and most students were mildly ill.
Why should the local stuff mutate slower than stuff on earth?
1) The world's population is enough to provide a pool for cold
viruses. It doesn't take new ones, the same pool of a few hundred
goes around. That's why you get fewer and fewer colds as you grow
older--infection grants immunity. (And that's why they can't come up
with a vaccine for the common cold--it's not *ONE* disease but a few
hundred.)
2) Flu is a better example of mutation--but even then it's still flu
viruses. It's not a totally alien virus changing to infect humans. To
jump from a totally alien ecosystem is much harder.