Evolutionary theories per se do not pose a theological problem to Catholic Faith; for instance, God could have designed a mutation/selection process to develop new life forms. St. Augustine speculated 15 centuries ago about whether God made Adam immediately or over a long period of time. Pope Pius XII made substantially the same comments in Humani Generis 50 years ago. Catholics have felt themselves quite free to speculate on this and thousand other questions since the founding of the Church, for they have always understood that strictly scientific questions are a matter of liberty, not dogma.
What does Catholic religious teaching entail?
(1) We acknowledge that created things--- however they were developed to their present forms --- show forth the intelligence and providental goodness of the Supreme Being: God the creator.
(2) We insist on monogenism, which (as opposed to polygenism) holds that all people now in existence have the same human inheritance. That means that a single couple became the ancestors of the entire human race.
(3) We know that human beings have a spiritual soul which is not the inevitable product of material forces. That means that human beings are not "programmed" by a strict materialistic determinism, but have an element of personal freedom.
(4) We hold human nature is seriously flawed by the inheritable effects of a primordial catastrophe ("the Fall") which our first ancestors brought upon themselves by their own actions (sin), and passed on to all their descendants.
None of these religious truths contradict the findings of scientific investigation. We are free to entertain any scientific theory, but not to embrace the assumptions of dogmatic philosophical materialism.
That business with Galileo would seem to indicate that "always" may not be entirely accurate.
(1) St. Augustine did not speculate that God could have created Adam "over a long period of time." I could be wrong - St. Augustine wrote about forty volumes of material and I haven't read it all, but I'm not buying this claim without specific citation.
(2) There is no such thing as a strictly scientific question, and the Church has indeed taught the faithful definitively on monogenism.
There are scientists who support polygenism and it is indeed a scientific question.
Well, you'll get no argument from me about these religious tenents...an Episcopalian, I share much of the same belief as my "Roman" (vice catholic) betheren. I do, however, point out that theological stalwarts such as St. Augustine, St. Thomas Aquinas and other thinkers had a rough time initially with the church in getting their thoughts accepted. And, I trust, you also have to admit that the apology that Pope John-Paul II issued to the late Copernicus, (who incidentally was a Polish bishop just like the apologetic pope), came a tad late.