Teachers’ conceptions about the origin of life in three Latin American countries with contrasting levels of secularism were analyzed: Argentina, Brazil, and Uruguay. A European survey questionnaire was used and the interpretation of the results drew on Barbour's four categories concerning the relationships of science and religion. A large majority of Argentinian and Uruguayan teachers were clearly evolutionist, even when believing in God, with no difference between Argentina and Uruguay. The majority of Brazilian teachers assumed a religious position about the (...) origin of life, being creationist or evolutionary creationist. Differences of Brazilian teachers’ conceptions may result from the higher percentage of evangelicals and lower proportion of agnostics/atheists. Brazilian Catholic teachers were more creationist than their Catholic colleagues in Argentina and Uruguay. Distinct patterns were found, but further research is needed to understand possible classroom impacts. (shrink)