Michael Shermer, in the Oct. issue of Scientific American, gives these arguments for being both a conservative Christian and a Darwinian:
1. EVOLUTION FITS WELL WITH THEOLOGY. What difference does it make when or how God created life (10 thousand or 10 billion years ago?, by natural forces or spoken word?) - All faiths, including Christians, should embrace modern science for what it has done to reveal the magnificence of the divine in a depth and detail unmatched by ancient texts.
2. CREATIONISM IS BAD THEOLOGY. The watchmaker God of intelligent-design creationism make God just a genetic engineer slightly more advanced than we are... this is belittling... an omniscient God must be above such human-like descriptions and constraints.
3. EVOLUTION EXPLAINS ORIGINAL SIN AND THE CHRISTIAN MODEL OF HUMAN NATURE. Like other social primates, we evolved within-group amity and between-group enmity. By nature, then, we are cooperative and competitive, altruistic and selfish, greedy and generous, peaceful and bellicose. Moral codes and a society based on the rule of law are necessary to accentuate the positive and attenuate the negative sides of our evolved nature.
4. EVOLUTION EXPLAINS FAMILY VALUES. In humans and other social mammals brain pathways and hormonal mechanisms have evolved to support attachment and bonding, cooperation and reciprocity, sympathy and empathy, conflict resolution, community concern and reputation anxiety, and response to group social norms. Religious moral codes reflect these evolved moral natures.
5. EVOLUTION EXPLAINS CONSERVATIVE FREE-MARKET ECONOMICS. Charles Darwin's "natural selection" is precisely parallel to Adam Smith's "invisible hand." Darwin showed how complex design and ecological balance were unintended consequences of competition among individual organisms. Smith showed how national wealth and social harmony were unintended consequences of competition among individual people. Nature's economy mirrors society's economy. Both are designed from the bottom up, not the top down.