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Homo naledi is an extinct species of hominin, provisionally assigned to the genus Homo. Discovered in 2013 and described in 2015, fossil skeletons were found in South Africa’s Gauteng province, in the Dinaledi Chamber of the Rising Star Cave system, about 800 meters (0.5 miles) southwest of Swartkrans, part of the Cradle of Humankind World Heritage Site. As of September 2015, fossils of at least fifteen individuals, amounting to 1550 specimens, have been excavated from the cave.
The species is characterized by a body mass and stature similar to small-bodied human populations, a smaller endocranial volume similar to Australopithecus, and a skull shape similar to early Homo species. The skeletal anatomy combines primitive features known from australopithecines with features known from early hominins. The individuals show signs of having been deliberately disposed of within the cave near the time of death. The fossils have not yet been dated.
Homo naledi was formally described in September 2015 by a 47-member international team of authors who proposed the bones represent a new species. Other experts contend more analysis and evidence is needed to support this classification; some experts think that the specimens might be Homo erectus.
Dating of the fossils has not been done as of 10 September 2015. The discovery team waited until after the research article was published before trying radiocarbon dating of the fossils because radiocarbon dating will have to destroy parts of the fossils.Radiocarbon dating can only date fossils which are 50,000 or fewer years ago, and can make a determination if the fossils are younger than 50,000 years old
Lee Berger said that the anatomy of H. naledi suggests it originated at or near the start of the Homo genus, around 2.5 million to 2.8 million years ago. The excavated bones may be younger.Tim White says that it is hard to know if the fossils are “much less than one million years old” or older.
Morphology is sometimes used to make some approximations about the temporal range of artifacts. Geologists think the cave in which the fossils were discovered is no older than three million years.
The bones were found lying on the cave floor or buried in shallow sediment. Two fossil dating techniques—dating fossils within volcanic ash by dating the ash, and dating fossils within layers of calcite flowstone deposited by running water by dating the flowstone—cannot be used because the fossils were not buried in volcanic ash or in flowstone layers. For example: in East Africa, volcanic ash layers, which are datable, helped to determine the age of fossils like Lucy at 3.2 million years old; Lee Berger himself used radiometric techniques to date his discovery of Australopithecus sediba bones found between two flowstone layers at another site.