More than 120,000 years ago, humans living in what is now Israel were collecting shells and threading them onto pieces of string—perhaps to be worn as jewelry, according to new research.
Scientists led by Daniella Bar-Yosef Mayer, an archaeologist at Tel Aviv University, found that naturally perforated shells discovered beneath human burials in the Qafzeh Cave in northern Israel show microscopic signs of wear consistent with having been strung together, reports Ariel David for Haaretz.
The team’s findings, published this week in the journal PLOS One, narrow down the invention of string to sometime between 160,000 and 120,000 years ago.
“The timing of the invention of strings is of significance beyond the desire to adorn oneself,” says Bar-Yosef Mayer in a statement quoted by the Jerusalem Post’s Rossella Tercatin.
Developing string was crucial for subsequent innovations including “hunting traps and fishing nets, archery for hunting with arrows, fishing using hooks, and other various practices related to sailing—for example, tying logs of wood to create rafts, as well as several uses connected to clothing,” the archaeologist adds.
As Siobhan Roberts reported for the New York Times in April, the earliest direct evidence of string is a 50,000-year-old cord fragment found in the Abri du Maras cave in southeastern France. The specimen is attributed not to Homo sapiens, but to Neanderthals, who inhabited the site between 90,000 and 42,000 years ago.
Since the braided organic materials used to make string and rope are rarely preserved, the researchers behind the new study relied on indirect evidence: namely, five ocher-laden shells found in northern Israel.
“Ocher was a substance to color various materials in red and was often used by prehistoric humans, possibly for painting their bodies, for processing hides, and more,” explains Bar-Yosef Mayer to Megan Marples of CNN. “Possibly, giving the shells a red color also had symbolic meanings.”
To determine the microscopic markers associated with different uses for the shells, the team conducted tests on modern clam shells, rubbing them against materials including sand, leather and wood, as well as stringing them together with wild flax cords. Abrasions and wear patterns produced by these experiments matched those found on the Qafzeh Cave shells, suggesting the latter were once hung on a string in close proximity to each other, reports CNN.
Per the study, natural damage at sea, rather than intentional drilling by humans, produced the holes that enabled the cave’s ancient residents to string the shells together.
The archaeologists also examined clam shells found at nearby Misliya Cave and dated to between 240,000 and 160,000 years old. The shells’ “battered condition” suggests Paleolithic people intentionally collected them, but they bear no holes or signs of being used in necklaces or other adornments, reports Kiona N. Smith for Ars Technica. Human-collected shells unearthed in similarly ancient cave sediment in South Africa have no perforations either.
The researchers theorize that the invention of string—which enabled shells to be “strung in order to be displayed,” according to the paper—accounts for ancient humans’ shift in preference from intact shells to those with naturally occurring holes.
Teresa Steele, a paleoanthropologist at the University of California, Davis, who was not involved in the study, tells Haaretz that the new paper suggests string and rope may “have much greater time depth than previously acknowledged.” She adds that the use-wear analysis featured in the study opens “a window into reconstructing organic technologies that are difficult to access in deep time.”