Despite considerable focus on evolution knowledge-belief relationships, little research has targeted populations with strong content backgrounds, such as undergraduate degrees in biology. This study (1) measured precertified biology and non-biology teachers' (n = 167) knowledge of evolution and the nature of science; (2) quantified teacher preferences for the teaching of creationism in schools; (3) examined the associations among knowledge and belief variables; and (4) contrasted the knowledge and beliefs of prospective biology teachers with those of non-biology teachers. Methodologically, teacher knowledge was quantified by using three measures and studied in relation to certification area, self-reported religiosity, personal conflict concerning science and religion, and completion of an evolution course. We found (1) generally low levels of knowledge of evolution and the nature of science--and high misconception magnitudes--in both biology and non-biology teachers; (2) comparable antievolutionary positions in biology and non-biology teachers: nearly half of the teachers in both groups advocated for the inclusion of creationism in school; (3) weak association between knowledge and preference/belief variables; and (4) no difference in preference for teaching creationism between those teachers who had taken an evolution course and those who had not. Overall, biology and non-biology teachers were found to display "mixed" and "novice naturalistic" evolutionary reasoning patterns. (Contains 2 tables and 4 figures.)