A direct ancestor emerges
In 1997, a team of paleoanthropologists led by Tim White discovered the remains of early modern humans near the village of Herto in the Middle Awash region of Ethiopia. The fossils were found in the Upper Herto Member of the Bouri Formation, a layer of sediment sandwiched between volcanic deposits. This geological context was perfect for dating. Using the argon-argon dating method on the volcanic rock, scientists established the age of the skulls at between 154,000 and 160,000 years old.
The discovery included three well-preserved crania: one nearly complete adult male (designated BOU-VP-16/1), a partial second adult, and one from a child estimated to be six or seven years old. These individuals possess features that are distinctly modern, such as a high cranial vault and a flat face, placing them firmly within our own species, Homo sapiens. However, they also retain some more robust, archaic traits, like a slightly larger and longer skull, which led their discoverers to classify them as a new subspecies: Homo sapiens idaltu. The word idaltu means "elder" in the local Afar language. The male skull, BOU-VP-16/1, has a cranial capacity of approximately 1,450 cubic centimeters, which is slightly larger than the average for humans today.
The first mortuary rites
The Herto skulls are particularly fascinating are the modifications found on their surfaces. The adult male and the child's skulls show distinct cut marks made by stone tools. These marks are not randomly placed; they suggest a systematic process of removing the flesh after death. More telling is the high degree of polish on parts of the bone, especially on the child's cranium. This is not the kind of polish that happens from natural processes like rolling in a river. Instead, it points to repeated, deliberate handling of the skulls long after they were defleshed.
This evidence is interpreted as one of the earliest known examples of a mortuary practice by Homo sapiens. The careful cleaning and subsequent handling of the skulls suggest a ritualistic or symbolic behavior surrounding death. These were not simply discarded remains. The Herto people lived along the shore of a shallow, freshwater lake that teemed with wildlife. Excavations at the site have uncovered thousands of stone tools, including hand axes, alongside the butchered bones of hippos and buffalo. This archaeological context shows a population adept at survival, who also took the time to engage in complex behaviors related to their deceased.