While not a part of Darwin’s theory of evolution, how the first living organism came to be is a big hurdle for the naturalist view. In fact one could argue that without a naturalistic explanation for how life on earth started then why do we need evolution.
I was not yet a teenager when I first read about the Miller/Urey experiments that took place beginning in 1953. Check it out here (http://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment ) I am thinking it was in either the late 50’s or early 60’s and I still remember how excited I was. Think about it, we were about to create life in the lab. It was not hard to believe such things back then. We were putting satellites in earth orbit. Soon we would be launching first animals and then men into orbit. Nothing seemed to be impossible. I was enamored with science and to a lesser degree I still am.
However, it has now been sixty years later and we still are no closer to solving the beginning of life problem. Yes we have been able to produce amino acids and other organic compounds in the lab but getting them to organize into life is still just a dream. We can find organic compounds in meteorites and interstellar clouds. Getting organics is not the problem. Organization is.
We are still a long way from getting simple RNA or DNA to organize in what we think the early earth’s atmosphere was. As far as we know with either RNA or DAN self-replication is impossible. And even if we were able to get either we still need to devise a cell membrane to hold everything together.
Really until the last quarter of the twentieth century we had not idea just how complex even the simplest cell is. Each and every cell is a miniature factory producing proteins, eliminating waste and taking in nourishment. Single celled organisms need some method of locomotion and cells in a body need to be able to cooperate with neighboring cells. I am not sure there is such a thing as a simple life form.
Another problem is that the early atmosphere does not seem to be life friendly. At the time life first appears, about 3.5 billion years ago, the atmosphere was mostly nitrogen, carbon dioxide, sulfuric gases and very little if any oxygen. With no oxygen there would have been no ozone layer and the young earth would have received most of the sun’s ultraviolet radiation which would have been harmful to any organic molecules. Add the constant bombardment of meteors and it seems that the deck is stacked against life forming. Yet it did.
With all these problems working against life spontaneously developing on earth some scientists such as Fred Hoyle have turned to the theory of panspermia to account for life on earth. Of course this does not answer the question of how life began all it does is push the origins further back in time to other planets which we will in all likelihood never visit if we can even identify likely candidates.
Panspermia also brings up another interesting problem. How did these original seed cells get to earth? The universe is approximately 13.77 billion years old. If these cells drifted through space to eventually settle on earth there just does not seem to be enough time. Our Voyager space craft will take at least 175,000 years to reach another solar system and that was with a rocket propelled start and using gravity slings to speed up. It is hard to believe cells could reach the 17 kilometer per second of the Voyager so their trip would have been much longer. Even then they would need to reach escape speed from their star. Still we have the issue if pure random luck that a cell could travel stellar distances, remain viable and travel to a planet that was hospitable to life.
The other alternative is that intelligent life seeded various life capable planets. The problem here is that it has taken life on earth the entire 3.5 billion years the earth has been in existence to develop a life form capable if travel in space and we have yet to reach another star. There is no reason the think if life really evolve via random mutations that other planets could have significantly beat our record. It took a few billion years for enough heavy elements to be formed in the stellar furnaces for life rocky planets to develop and life to begin. Once again we run into a time problem. This still leaves the problem of finding planets capable of sustaining life and traveling to them. As always time is a factor. Having viable cells travel stellar distances and landing on earth seems like the ultimate lottery win. The irony of some other life form seeding life on earth is that this is just a backdoor intelligent design. How did life originate on earth? An intelligent being put it there.
The development of life on earth without an intelligent agent just seems so lucky. So dependent on randomness that I for one find it much easier to believe in God. Once again to quote the title of Norman Geisler’s book, I just don’t have enough faith to be an atheist.
Next time I will look at human evolution and the evidence for it and against it.
Have a blessed day,