History of aspirin other studies from the 1960s to the 1980s established aspirin's efficacy as an anti-clotting agent that reduces the risk of clotting diseases. Aspirin sales revived considerably in the last decades of the twentieth century, and remain strong in the twenty-first with widespread use as a preventive treatment for heart attacks and strokes. Medicines derived from willow trees and other salicylate-rich plants have been part of pharmacopoeias at least dating back to ancient Sumer. The Ebers Papyrus, an Egyptian medical text from ca. 1543 BCE, mentions use of willow and myrtle (another salicylate-rich plant) to treat fever and pain. Willow bark
Tree of life on the Turtle's Back", explains the origin of the land in which a tree of life is described. According to the myth, it is found in the heavens, where the first humans lived, until a pregnant woman fell and landed in an endless sea. Saved by a giant turtle from drowning, she formed the world on its back by planting bark taken from the tree. The tree of life motif is present in the traditional Ojibway cosmology and traditions. It is sometimes described as Grandmother Cedar, or "Nookomis Giizhig" in Anishinaabemowin. In the book Black Elk Speaks, Black Elk, an