WARSAW, POLAND—A 7,000-year-old set of sharp, gutter-shaped bone tools has been uncovered in northern Sudan’s Letti Basin by researchers from the Polish Academy of Sciences, according to a Science in Poland report. The implements were recovered from a grave that held the remains of an elderly man covered with fragments of animal skin colored with red ocher. A small bowl in the grave also held traces of ocher and five bone blades of varying sizes. “Given the characteristic shape of the blades, they could have been used to bleed cows, similar to modern African shepherds, such as the Maasai. Without any harm to the animals, cows’ blood is drunk on special occasions, usually mixed with milk. It would be the oldest known record of this type of practice,” explained research team leader Piotr Osypiński. A second grave in the cemetery, he added, held the remains of a young man who had been buried on his right side in a flexed position with a stone palette for rubbing ocher and two similarly shaped bone blades. He had also been covered with an animal skin soaked in red ocher. Clusters of cattle bones have also been found in the cemetery. To read about the Nubian necropolis of Sedeinga, go to "Miniature Pyramids of Sudan."