Father to the Man — John Gribbin

Nobel Prize-winning scientist Richard Lee has stirred up fanatical religious hatred with his controversial theory that chimpanzees and humans may have shared a common ancestor as little as three million years ago. When this hatred loses him both his reputation and his beloved colleague Marjorie, Lee retreats into hiding with his experiments and with Adam, an apelike creature thought by some to be Lee's own deformed love-child, or even a kind of Frankenstein's monster.
But Adam is growing up, and the astonishing secret of his genetic parentage cannot remain secret forever, especially once investigative journalist Louise Henderson scents a story in the remote Norfolk village where Lee has gone to earth.