....... just a thought..... and albeit a small one. We know that certain bacteria were once susceptible to certain types of antibiotics...now they can thrive on those antibiotics..Some were able to adapt and modify while others that had specific cell wall structures or enzymes were able to thrive. Now the hand of God created "the heaven and the earth and all the living creatures". He also gave us the ability to adapt and multiply. All the gifts and options that we have are of his doing. The age of the Earth, the "first" man, and all the other questions about our development of "consciousness" and self awareness fall within the "belief in God".
The other thing is that even if the universe EXPLODED, that doesn't mean that his hand wasn't the one directing things.
I believe that God created the heavens and the earth, and humankind and all creatures. How exactly He did it, we won't know until we get to heaven itself.
I'm not sure they 'adapted'. They were ALREADY in the population germs that we were trying to kill, except they were not susepible(sp?) to the killing agent.