God and Why Things Happen

I had an interesting discussion on a car trip last night with my wife Sue and niece, Jenn. We had started with the question of life off the Earth, and touched on parallel universes and extra dimensions, God and science. At one point I mentioned the tube worms and other creatures living around the deep sea vents.
Sue: What is the purpose of them being there?
Rob: Do you mean what role do they play in their little ecosystem?
Sue: No, what is the reason they are there?
Rob: Evolution doesn’t happen for a reason, that is, in order to fulfill something. Like giraffes didn’t evolve long necks in order to eat the leaves of tall trees. Its just that longer necked creatures were able to get more food, so stayed healthy, and had more babies. So over the long run, a long-necked creature evolved.
Jenn: So you don’t believe there was a purpose to their evolution.
Rob: “Believe?” Good word, Jenn. You are asking a philosophical question: what is my philosophy or religious position on the matter. Not a question of science.
Jenn: No, no. Science. If giraffes didn’t evolve long necks there would be more leaves left on the trees. They would shade the ground, changing the temperature. They would fall and rot and change the pH. There’s be a different ecosystem.
Rob: Right. Good point. That’s why we have to be careful because when we engineer a change in the ecosystem, a million other things are affected.
Jenn: Right, like adding rabbits to Australia, or using pesticides. So can’t the purpose of the giraffes be that they are needed for that ecosystem?
Rob: But let’s for a moment assume that there are no giraffes. You would say to me “The reason there are no long-necked creatures is that they would eat the high leaves, there would be more sunshine, so the ground would be warmer at the base of the tree. There would be fewer leaves to rot, and the pH would change.
Jenn: (laughs) Same argument.
Rob: Right. Your original argument was, basically, if there are no giraffes, things would be different. When that argument can be used both for and against the point being examined, that argument is valueless as a scientific statement.
Jenn: I see that.
Rob: You could make it into a valid philosophical argument, though. A religious person could say, for example, that if there were no giraffes, conditions would be different and the difference would be bad. Since God would not have wanted the conditions to be bad, God wouldn’t have allowed that (i.e. no giraffes) to happen, and would have created/evolved giraffes in the first place.
The problem with this argument, though, is that, for consistency, it must be applied everywhere. You could say that the malaria mosquito or the TB virus must have been created/evolved for a purpose. So why are we (even “good” religious people) contributing money to eradicate these creatures? Might not we be acting against God’s will?
There are a couple of ways out of this conundrum. One is to say that we are part of God’s creation/evolution, so our purpose was to alter the ecosystem (for the good) by wiping out the bad bugs. Unfortunately, this argument also has too wide a range, because it could be used by the people eradicating the rainforests and polluting the environment, too.
Another escape is the “free will” argument: God gave us free will to do our best to determine what’s good and what’s bad. We see that wiping out giraffes is bad, but wiping out TB is good. (That leaves the question about why God allowed the TB in the first place, if not to test us when we develop the capability of eradicating it. (This heads towards “Why do bad things happen to good people?”, perhaps the deepest, most important religious question.)
Sue: Rob! Pay attention. You’re heading to Niagara falls!
Rob: [cutting across two lanes highway traffic, and driving on the shoulder until we can get into the correct lane] Sorry.