Science proceeds by evaluating evidence and postulating a governing mechanism for that evidence. As more data fits the mechanism, we may call our postulated mechanism a 'theory'. As the theory is applied repeatedly with successful prediction of results, we have a law. When does the theory become a law? Certainly when we can repeatedly get accurate day-to-day numerical predictions based on an equation-based numerical law such as Ohm's law. Evolution is far more complex and far harder to tie down to a numerical model, of course. So is cosmology; the big picture is beyond foreseeable numerical modelling, although some parts of the picture can be modelled. So science is about the plausibility of postulated mechanism. The postulated mechanism on its own is not necessarily good science of course. And here currently accepted 'science' varies widely.
Now science gets even more subjective when it comes to the relational and psychological arena. A former colleague of mine pointed out that 'ologies' are the more subjective end of science. Yet these areas bear strongly on how religious people such as myself think. It is one thing to talk about the plausibility of a postulated mechanism, here meaning evolution, from the scientific and statistical standpoint. It is another to discuss the character and relational nature of God and the implications they have for that theory. Why do I believe that God did not use evolution by natural selection to develop species into higher forms? Here I am talking about the intent of God, morally speaking, and not about the plausibility of the science. The 'science' has big problems, for sure. But surely the creator redeemer Christ of Paul's Letter to the Colossians would not use natural selection to do a neat experiment in bio-engineering. I do not believe God would have used natural selection in the beginning because it involves cruelty in the form of predation and suffering.
Of course, today, the selfish instinct for survival is readily seen in the animal kingdom, so how do we explain this? I will return to that question in a minute.
What is my own explanation for the physical evidence? I am inclined to believe that God used individual acts of special creation, i.e. of intelligent design. Built into these designs is the capacity to diversify through the reproductive process. However the degree of diversification possible within a created species is constrained, again by design. That diversification is of course a basis for selection to work on. However I do not believe Christians can reconcile predation and selective survival with the God of love, unless sin had already entered the world. This is why I believe that, at least for the present episode of creation, the one described in Genesis 1v2 onwards, that species were made by acts of special creation.
I will now return to the cruelty we see manifested today in the creation. The Bible teaches that the spiritual climate of planet Earth was violated in an event theologians and Bible scholars call the Fall. Here, Satan, a rebellious spiritual being, influenced man in the direction of strife. Man disobeyed God's specific prohibition. He succumbs to temptation. Man is no longer at peace and rest. Straining to better oneself enters into man's heart for the first time. The animal kingdom is under Adams's jurisdiction. What happens to man therefore affects the biosphere in general. I think God allowed psychological and physical changes into the animal kingdom at this time which reflected the cataclysm in the human governance of Earth. Predation entered at the Fall, when sin entered into the physical world through Adam.
What about the age of the earth itself? I do not necessarily believe in the widely accepted inference that the earth is around 4.5 billion years old. Even the exactitude smacks of self-deception in the scientific community to me. However I accept that the world looks hundreds of millions or billions of years old by radiometric dating and other means. The accepted dating could be badly out, but not by enough to satisfy a young earth creationist. Some say God made the Earth look old to mislead our minds to prove our faith. I cannot accept that. I, and many others, got saved by a process which involved, amongst other things, looking logically at the evidence for the resurrection. Faith is not a call to throw logic away. It is a call to review and revise which facts your logic works on.
My present conclusions on origins? Taking all these factors discussed into account, I find it hard to reconcile the apparent approximate age of the Earth derived from radiometric dating with a once only, and recent, creation. God could have populated the earth in a very short time by acts of special creation, of course. I believe he probably did, as described in Genesis. But the fossil record does speak of much more ancient extinct species including predators. It seems to me likely that there were previous episodes of creation on earth, episodes that may also reflect falls from the perfect will of God due to rebellion and disobedience in the created orders of the times. These species were then wiped out in judgement. These episodes would then of course be recorded, to a degree, in the fossil record. Genesis 1v2 says that 'the Earth was (or became) void and without form'. As an illustration of this,when we look at the moon through magnifying optics, we see a desolate, and possibly desolated, place. Buzz Aldrin, the second man to walk on the moon, called it 'magnificent desolation'. God could have caused the Earth to become 'without form and void' in a similar way.
So my doubts about evolution start from a belief in the God of the Bible, and his moral and emotional nature. While he steers the evil for his own purposes, he is not the wilful cause of evil or entities who have become evil, such as Satan. However in addition I have plenty of scientific reasons why I don't believe the theory of evolution by natural selection, at least not in its frequently accepted, all embracing, scope of application.