They believe it, that settles it. Think "peer pressure."

STATEMENT BY IOWA FACULTY ON HF 183:
THE EVOLUTION ACADEMIC FREEDOM ACT

We, the undersigned members of institutions of higher learning in Iowa, urge our legislators to reject passage of "The Evolution Academic Freedom Act" (HF 183) introduced by Rod Roberts (R-Carroll). The language of this bill comes primarily from the Seattle-based Discovery Institute, which has conducted lobbying efforts and political activism against the teaching of evolution since 1994.

Evolution is as established a scientific theory as any other theory in science.  It is misleading to claim that there is any controversy or dissent within the vast majority of the scientific community regarding the scientific validity of evolutionary theory. Since there is no real dissent within the scientific community, then "academic freedom" for alternative theories is simply a mechanism to introduce religious or non-scientific doctrines into our science curriculum.

Similar efforts to undermine the teaching of evolution in schools repeatedly have been found to be unconstitutional, something witnessed most recently in Kitzmiller v. Dover (2005) in Pennsylvania.

We, therefore, urge our legislators to recognize HF183 as part of a long history of creationist assaults on science education, and reject passage of this bill.

It is therefore the intent of the general assembly that this Act be construed to expressly protect the affirmative right and freedom of every instructor at the elementary, secondary, and postsecondary level to objectively present scientific information relevant to the full range of scientific views regarding biological and chemical evolution in connection with teaching any prescribed curriculum regarding chemical or biological evolution. (italics added)

On the other hand . . .