What is the oldest known human hair?

Research has fascinatingly uncoiled the trail to the oldest known human hair, with a landmark discovery in Gladysvale cave, South Africa. Researchers have found fossil hairs of probable human origin, surpassing the previous oldest record by an astounding 200,000 years. The previous record was held by a 9,000-year-old Chinchorro mummy from northern Chile. The new-found hairs were found encased within a coprolite, or fossilized dung, of a brown hyena (Parahyaena brunnea), dating back to a period between 195,000 to 257,000 years ago, the Middle Pleistocene era.

The exciting discovery of the oldest known human hair was initially chronicled in the Journal of Archaeological Science, Volume 36, Issue 6, in 2009 and later followed up with a more detailed analysis in 2013. This intriguing find not only sheds light on the existence of early hominins but also strengthens the hypothesis that hyenas may have played a role in accumulating some of the early hominin remains found in some cave sites. Furthermore, this discovery presents a fresh lens through which we can view Pleistocene mammals in the Sterkfontein Valley of Africa.

The identification of these ancient hairs was no mean feat. It required rigorous assessment of their microscopic structural attributes. A key feature used in identifying hair is the cuticular scales, whose variations between different species are of significant taxonomic importance. The scale patterns can differ widely, and their position relative to the hair’s longitudinal direction is also a crucial identifying feature. These hairs’ patterns were then compared to a collection of hairs from indigenous southern African mammals.

This in-depth examination led to the tentative identification of the hair belonging to the family primates, with human hair as the most likely candidate. This identification was further supported by the environment surrounding the discovery: the size, shape, and contents of the latrine strongly suggested the involvement of a brown hyena. Considering the high representation of hominins in the region, it isn’t overly surprising that the hairs are human in origin. The hyenas in the region are known to scavenge more than hunt, supporting the likelihood that the hair was not a result of any direct predation.

Hair preservation over such extended periods of time is unusual due to the lack of suitable preservation conditions. Fossilized mammalian hairs are exceedingly rare, with the oldest fossil hairs reported from China, dating back to the Early Cretaceous period. The hyena’s fossilized dung was something of a scientific windfall, as meat-eater dung makes for an ideal hair preservative. The oldest known mammalian hairs are found in carnivore feces, Siberian permafrost and/or amber. The high calcium content in the fossilized dung, plus the calcium-rich water dripping from the cave roof, is believed to have facilitated the fossilization process at Gladysvale.

Remarkably, the hair fibers found in the fossilized dung were also themselves fossilized. Hair is mostly made up of the fibrous protein keratin, which is extremely resistant to decomposition and enzymatic digestion, owing mainly to the presence of disulphide cross linkages of the amino acid cysteine, the most common amino acid protein molecule found in hair. In effect, the fossilized material around the hair sealed the fiber in a cast. As the hair itself degraded away over thousands of years, it was replaced by calcium deposits taking up the same shape as the original hair. Element analysis showed total replacement of keratin by calcium carbonate, confirming that the Gladysvale hairs are high-resolution casts and the amino acids or DNA have not been preserved. Strictly speaking then, the oldest known actual human hair record is still held by the 9,000-year-old Chinchorro mummy.

Never-the-less, this discovery marks a pivotal moment in our understanding of human antiquity, offering a vivid glimpse into our prehistoric past. It gives a rare insight into the environment in which archaic and modern humans lived in the interior of the African subcontinent. The finding of human hair provides evidence of inland occupation by archaic Homo sapiens, such as Homo heidelbergensis, or of the first anatomically modern humans. Other hair found in the fossilized poo came from warthog, impala, zebra, and kudu suggesting humans lived alongside and probably hunted, these animals.

As these fossil hairs from the Gladysvale cave stand as tangible reminders of our ancient lineage, it reiterates the unceasing march of time and the inevitable imprints it leaves behind. Through their resilience and silent testimony, these hairs weave a story of early human existence in the heart of the African subcontinent, contributing invaluable threads to the vast tapestry of human history. As we continue to unravel the past, the significance of such discoveries remains pivotal, extending our knowledge of our ancestors and the world they inhabited.

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