Just something to throw into this thread. Evolution has a sort of bait and switch attached to it in my experience. People defend a version of evolution as a very narrow mutation of genes and defend it by noting the research and observation that has happened about different animals/plants/bacteria. Then once you say that you believe that version of evolution, you're suddenly saddled with the idea that evolution is a blanket explanation for life coming into existence in the first place (abiogenesis), extreme speciation, and that all life came from one or a few unicellular creatures a billion years ago. The evidence for this is questionable, but the questioners are shot down, and before anyone posts a link to talkorigins, I have read most of the site, and find it unconvincing. Evidence that is millions of years old is sparse, and theories spinning that "new" attributes arose from the natural selection of a set of random mutations gives rise to dozens of unanswered questions about genetics.
Given that there have been so many times when scientists thought they knew everything and then were given whiplash when the universe suddenly became a whole different story (classical physics->relativity->modern/quantum physics->string theory?) I don't want to rest my mind on a philosophy that assumes that scientists understand everything. When life itself can be described and we aren't poking around in the dark about genetics, then you can talk to me about the origin of life. Before then, study genetics, abiogenesis, or whatever, but don't prosthelatize evolution unless you're willing to admit it's mainly philosophy with some science mixed in. Don't try and tell me evolution is science, because I have seen science, I. I know about research and that research can be credible and can be chasing after a popular fad.
Think logically or philosophically about evolution. Each stage must be directed by something that supercedes it. To just have random mutation without some selecting criteria to direct it, then you get nothing. To have the selectors also not have a criteria, you get chaos. Without a system ripe to perform the selection, you get nothing. The last point refers to the chemistry itself being capable of sustaining life. Such a chemistry isn't necessary, it simply exists that way. Scientists are prepared to just accept that chemistry is just the way it is, but not that biology is just the way it is. To not accept a science in this way is to push philosophy in science, and a weak philosophy at that. To impute that life existing at one time necessarily caused life at another point is a historical question, not a biological one. Maybe it is fit for archaeology or palentology, but these are simply descriptive sciences, with less weight than physics, chemistry and biology. Biology itself was a mere descriptive science before genetics, and now we may be coming to the point of an explanation with a set of rules as neatly placed as a periodic table. However, I am afraid that evolutionary philosophy is so entrenched in biology that a finding that revolutionizes biology that contradicts evolution will be stalled in the annals of the published research racket. Many scientific discoveries are made long before they are allowed to be published, and scientific progress tends to be made on the deaths of the adherents to discarded theories. This doesn't mean that there aren't a lot of crackpot creationist theories, but creationists don't have a monopoly on crackpots, and evolutionists don't have a monopoly on intellectuals or scientists.
So while evolution might be supported by reams of research in published journals, remember this is the science evolution, and not the philosophy evolution. Don't think that it explains all life, don't believe for a moment that the diversity of life will necessarily or even likely be explained within the general framework of the dozen or so theories under the name evolution. For random mutations to put forth the multiple on multiple precise mechanisms to make a multicellular organism work without the mutations destroying the creature and then to have multiple organisms work together requires an exhaustive understanding of life down to its last atom.