The painter Georgia O'Keefe spent 25 years making animal bones a major theme of her work. She would collect bone specimens during her walks in the New Mexico deserts, and claimed that her skull paintings expressed what she felt about the desert. Her Horse's Skull with Pink Rose, shown here, was also called “Life and Death”. O'Keefe is one of many artists, among them Alfred Stieglitz, Charles Sheeler and Joseph Stella, whose contributions to the creation of an art that was both American and modern are considered in The Great American Thing: Modern Art and National Identity, 1915–1935 by Wanda M. Corn (University of California Press, $50, £30).