A public radio station in Berkeley, Calif., said it canceled a live discussion and book signing with the evolutionary biologist and noted atheist Richard Dawkins because of his past comments criticizing Islam.

Mr. Dawkins was to promote his new book, “Science in the Soul: Selected Writings of a Passionate Rationalist,” before an audience of hundreds of paying ticket holders on Aug. 9. The event was also to be a fund-raiser for its host, the radio station KPFA.

The station sent an email to ticket holders on Thursday that praised the book but apologized for not having “broader knowledge” of his views much earlier. It added that Mr. Dawkins had hurt people with “his tweets and other comments on Islam.”

The email was quoted in full by Mr. Dawkins in an open letter that criticized the station’s decision on Friday.