Ancient Genome Discovered

While it doesn’t seem like a 2,330 year-old skeleton from the southernmost tip of Africa could tell us a lot about our genetic ancestry, it actually can reveal a great deal.  This skeleton’s DNA profile is one of the “earliest diverged” found to date in a region where modern humans are believed to have originated from some 200,000 years ago.  The man’s maternal (or mitochondrial) DNA was Michael weilert MD cave paintingssequenced to effectively provide clues to early modern human prehistory and evolution.  This mitochondrial DNA provided the first evidence that humans originally came from Africa, and helped us map a figurative genetic tree, with all branches deriving from a common “Mitochondrial Eve”

About 4 years ago, archaeologist Andrew Smith from the University of Cape Town discovered the skeleton at St. Helena Bay in 2010, very close to the site where 117,000 year old human footprints had been found.  After contacting various experts in biological anthropology and African genomes, the skeleton was examined by Alan Morris of the University of Cape Town.  Morris discovered that the man was a “marine forager”, and a bony growth in his ear canal suggested that he spent some time diving for food in the coastal waters, while shells carbon-dated to the same period that he died that were found near his grave confirmed his diet of seafood.  He was estimated to be in his fifties.  According to DNA extracted from the man’s body, this man’s lineage, now assumed extinct, was the most closely related to “Mitochondrial eve”

The researchers know that this man pre-dates migration into the region, which sheds new light onto early humans.  This means that the marine hunter-gatherer carried a different maternal lineage to these earlier migrants, which contains a DNA variant that has never before been seen.  Due to this, the study give a baseline against which historic herders at the Cape can now be compared.  This skeleton comes from an ancient lineage that had broken off early in modern human evolution, and remained geographically isolated.  This would help to significantly contribute to refining the human reference genome.