A word about evolution and creationism

I understand, although I do not share, the mistrust of science's infalibility by this country's radical Christian right . The past century gave us enough examples of how science, even in its Nobel prize parnassum, can be easily corrupted by ideology and by politics. Aryan physics and Lisenkoism, among others, have shown that lies can pass as legitimate science when properly expressed in scientific language. People, often uncritical and improperly educated, have the same blind faith in science or what is presented as such as the faith of medieval man in saints' relics. Nevertheless, what I understand even less is their fanatical attachment to the letter of Scripture. If they can read most of the Pentateuch allegorically, allowing them to do away with the eating of pork and shrimp and the Israelite sacrificial system, why do they insist so staunchily and arbitrarily in the literality of the seven days of Creation? If they defend so vocally the allegorical reading of most of the Hebrew Bible, why are they not willing to entertain even the possibility of an allegorical reading of this particular passage? Is it the obstinacy of their fundamentalism or is their stubborness a last stand against the possibility of another source to the truth other than revelation?