Rachel Carson was an American marine biologist and nature writer whose writings are credited with advancing the global environmental movement. Carson started her career as a biologist in the U.S. Bureau of Fisheries, and became a full-time nature writer in the 1950s. Her widely praised 1951 bestseller, The Sea Around Us, won her financial security and recognition as a gifted writer. Her next book, The Edge of the Sea, and the republished version of her first book, Under the Sea Wind, were also bestsellers. Together, her sea trilogy explores the whole of ocean life, from the shores to the surface to the deep sea. In the late 1950s, Carson turned her attention to conservation and the environmental problems caused by synthetic pesticides. The result was Silent Spring (1962), which brought environmental concerns to an unprecedented portion of the American public. Silent Spring spurred a reversal in national pesticide policy — leading to a nationwide ban on DDT and other pesticides — and the grassroots environmental movement the book inspired led to the creation of the Environmental Protection Agency. Carson was posthumously awarded the Presidential Medal of Freedom by Jimmy Carter.