born May 27, 1928, Barnton, Edinburgh, Scot. Scottish composer. She studied with Nadia Boulanger and Aaron Copland, and she later taught at the University of California at Santa Barbara (1970-78) and elsewhere in the U.S. She has written a number of dramatic concertos, some of which reflect her interest in music's spatial dimension, but she is best known for her operas, including The Voice of Ariadne (1973), Mary, Queen of Scots (1977), and Simon Bolívar (1995)