Wheelers is a hard science fiction novel written by English mathematician Ian Stewart and reproductive biologist Jack Cohen. The book was originally released in hardcover form in the year 2000, and a more common paperback printing was begun in 2001. It has enjoyed modest commercial success and is perhaps best known for its conceptions of alien zoology and intelligence—hallmarks of Cohen's work as a consultant on exobiology for books, movies, and television. Though this is the first time the pair has written a fictional narrative of their own, both Stewart and Cohen have worked continually with friend and fantasy author Terry Pratchett on his best-selling Discworld series. Source: Wikipedia (en)