An ancestor's unusual shape.In 1924, anthropologists working at the Sudanese site of Singa found the upper portion of a skull embedded in rock along the Nile River Nile River Arabic Bahr al-Nil River, eastern and northeastern Africa. The longest river in the world, it is about 4,132 mi (6,650 km) long from its remotest headstream (which flows into Lake Victoria) to the Mediterranean Sea. . Some investigators consider the Singa skull an example of an anatomically modern human ancestral to Khoisan hunter-gatherers still living in Africa. Others argue that the specimen represents a more primitive, or archaic, form of modern humans that lived around 100,000 years ago. New evidence supports the latter view, reports Christopher B. Stringer string·er n. 1. One that strings: a stringer of beads. 2. Architecture a. A long heavy horizontal timber used as a support or connector. b. A stringboard. of the Natural History Museum in London, England. Measurements of the Singa skull's shape more closely match those from archaic Homo sapiens archaic Homo sapiens Relating to or being an early form or subspecies of Homo sapiens, anatomically distinct from modern humans. Neanderthals in Europe and Solo man in Asia are usually classed as archaic humans. fossils than those from anatomically modern humans, Stringer asserts. Preliminary efforts to date two animal teeth found in the same sediment as the Singa skull place them between 97,000 and 160,000 years old. Some type of disease may have altered the shape of the Singa skull and thus misled earlier investigators, Stringer contends. The brain case appears low for an archaic human and shows significant widening toward the middle. Computed tomography Computed tomography (CT scan) X rays are aimed at slices of the body (by rotating equipment) and results are assembled with a computer to give a three-dimensional picture of a structure. (CT) scans reveal thickened thick·en tr. & intr.v. thick·ened, thick·en·ing, thick·ens 1. To make or become thick or thicker: Thicken the sauce with cornstarch. The crowd thickened near the doorway. 2. bony tissue in central skull bones that may have contributed to the specimens shape, he maintains. The right side of the fossil sports a small hole where the bones of the middle ear normally lie, Stringer notes. He considers this an inborn inborn /in·born/ (in´born?) 1. genetically determined, and present at birth. 2. congenital. in·born adj. 1. Possessed by an organism at birth. 2. defect. "This fossil has unusual features, and we need to understand its pathologies much better," Stringer says. |
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