Francisco Ayala, a former president of the American Association for the Advancement of Science, has been awarded a £1 million prize for work of a spiritual nature.
Ayala, an evolutionary geneticist and molecular biologist, is also a former Dominican priest who hails religious belief as a unique means of understanding the meaning of life.
He was awarded the Templeton Prize, which aims to reward "an exceptional contribution to affirming life's spiritual dimension" at the US National Academy of Sciences (NAS).
Spanish-born Ayala is currently the Donald Bren Professor of Biological Sciences at the University of California. He has spent more than 30 years defending the view - commonplace in Europe - that science and religion each have their place, and that both are damaged if one invades the territory of the other.
"If they are properly understood," he said, "they cannot be in contradiction because science and religion concern different matters, and each is essential to human understanding."
In 1981 he served as an expert witness in a pivotal federal court challenge that led to the overturning of an infamous Arkansas law mandating the teaching of creationism alongside evolution.
The award has caused some controversy amongst scientists, who are concerned that hosting the event at the NAS may give the John Templeton Foundation an undeserved scientific respectability.
Previous award winners cover quite a range, from physicist and mathematician Freeman Dyson to television evangelist Billy Graham.
Ayala says he plans to give much of the prize to charity.