Tucker. John Hoyland, Howard Hodgkin, John Walker, Ian Stephenson, Robyn Denny, John Plumb and William Tillyer were British painters who emerged at that time and who reflected the new international style of Color Field painting. During the 1960s another group of British artists offered a radical alternative to more conventional artmaking and they included Bruce McLean, Barry Flanagan, Richard Long and Gilbert and George. British pop art painters David Hockney, Patrick Caulfield, Derek Boshier, Peter Phillips, Peter Blake (best known for the cover-art for Sgt. Pepper's Lonely Hearts Club Band), Gerald Laing, the sculptor Allen Jones were part of the sixties art scene as was the British-based American painter R. B. Kitaj. Photorealism in the hands of Malcolm Morley (who was awarded the first Turner Prize in 1984) emerged in the 1960s as well as the op-art of Bridget Riley. Michael Craig-Martin was an influential teacher of some of the Young British Artists and is known for the conceptual work, An Oak Tree (1973). Contemporary art Post-modern, contemporary British art, particularly that of the Young British Artists, has been said to be "characterised by a fundamental concern with material culture ... perceived as a post-imperial cultural anxiety". The annual Turner Prize, founded in 1984 and organized by the Tate, has developed as a highly publicized showcase for contemporary British art. Among the beneficiaries have been several members of the Young British Artists (YBA) movement, which includes Damien Hirst, Rachel Whiteread, and Tracey Emin, who rose to prominence after the Freeze exhibition of 1988, with the backing of Charles Saatchi and achieved international recognition with their version of conceptual art. This often featured installations, notably Hirst's vitrine containing a preserved shark. The Tate gallery and eventually the Royal Academy also gave them exposure. The influence of Saatchi's generous and wide-ranging patronage was to become a matter of some controversy, as was that of Jay Jopling, the most influential London gallerist. The Sensation exhibition of works from the Saatchi Collection was controversial in both the UK and the US, though in different ways. At the Royal Academy press-generated controversy centred on Myra, a very large image of the murderer Myra Hindley by Marcus Harvey, but when the show travelled to New York City, opening at the Brooklyn Museum in late 1999, it was met with intense protest about The Holy Virgin Mary by Chris Ofili, which had not provoked this reaction in