Francis Willughby (sometimes spelt Willoughby) FRS (22 November 1635 – 3 July 1672) was an English ornithologist and ichthyologist, and an early student of linguistics and games. He was born and raised at Middleton Hall, Warwickshire, the only son of an affluent country family. He was a student at Trinity College, Cambridge, where he was tutored by the mathematician and naturalist John Ray, who became a lifetime friend and colleague, and lived with Willughby after 1662 when he lost his livelihood through his refusal to sign the Act of Uniformity. Willughby was elected as a Fellow of the Royal Society in 1661, then aged 27.