Our species’ early history as a unique giant ape known as Homo sapiens must be rewritten once more. With the help of a massive volcanic eruption that shook Ethiopia hundreds of thousands of years ago, the remains of the oldest documented Homo sapiens fossils in eastern Africa have been re-dated. According to the latest discoveries, the remains’ minimum age is now around 233,000 years old, which is 36,000 years older than previously estimated.
In a statement given to IFLScience, co-author Dr. Aurélien Mounier of the Musée de l’Homme in Paris remarked, “The revised date estimate, de facto, makes it the earliest uncontested Homo sapiens in Africa.” The research was published in the journal Nature today. The remains of Omo I, widely considered to be one of the earliest Homo sapien fossils ever discovered, were first discovered in the Omo Kibish Formation in southwestern Ethiopia in the 1960s by a team of researchers led the University of Cambridge (by a team from the Kenya National Museums led by trailblazing fossil hunter Richard Leakey, who died earlier this month).
Scientists can estimate the age of fossils by dating sediment layers, and as the technique improves, so does the accuracy. Early Homo sapiens fossils can be difficult to date and, at times, highly disputed. The unexpected finding of 300,000-year-old H. sapien remains in Morocco was one of the most dramatic events of recent years. However, not everyone accepts that these bones are actually Homo sapien because they have a skull morphology that is significantly different from current humans.
Nonetheless, the Omo I remains are unquestionably the oldest Homo sapien remains in East Africa, a pivotal area in the emergence of our species frequently referred to as the “cradle of humanity,” and potentially the oldest uncontested Homo sapien remains in Africa.
Dr. Mounier noted, “Unlike other Middle Pleistocene fossils supposed to belong to the early phases of the Homo sapiens lineage, Omo I has clear modern human traits, such as a tall and globular cranial vault and a chin.” Previous attempts to date Omo I based on the adjacent volcanic ash layer estimated the remains were roughly 197,000 years old. However, this age has long been disputed because the ash is too fine-grained to be correctly dated using traditional methods.
The latest study employed a somewhat different technique, linking the surrounding volcanic deposits to a massive explosive eruption of the Shala volcano in the Main Ethiopian Rift in the late Middle Pleistocene, about the time that H. sapiens began to emerge.
According to a geochemical study, the remains were discovered deeper than a layer of ash from a 230,000-year-old eruption, indicating that they were possibly older. They are roughly 233,000 years old, according to the researchers, setting a new minimum age for Homo sapiens in eastern Africa.
The researchers believe that this is only the beginning of the saga and that the oldest Homo sapiens in eastern Africa have yet to be located and completely understood. Professor Christine Lane, study co-author and head of the Cambridge Tephra Laboratory, said, “Our forensic approach provides a new minimum age for Homo sapiens in eastern Africa, but the challenge remains to provide a cap, a maximum age, for their emergence, which is widely believed to have occurred in this region.” “It’s likely that subsequent discoveries and investigations will push our species’ age back even further.”
