Humans May Have Kept Souvenirs 500,000 Years Ago, Study Suggests

Ancient Humans May Have Saved Pebbles to Remember Their Lives

Small, round, colorful pebbles found in an Israeli cave show no sign of practical use, yet early humans carried them in again and again over roughly 200,000 years, starting around 400,000 years ago. A new paper argues that these pebbles, along with unusual objects from sites across Africa, Europe, and Asia, may show early humans keeping souvenirs as far back as about 500,000 years ago, long before writing existed.

Published in Evolutionary Anthropology: Issues, News, and Reviews, the paper from a team of archaeologists and neuroscientists proposes that keepsakes worked as outside memory aids. Over time, that habit may have pushed human evolution toward the brain systems that hold a person’s life story and sense of self.

Earlier research mostly treated ancient collected objects as social signals, such as markers of status. This paper looks earlier and gets personal: objects kept to remind one individual of a place, event, or person, like a beach stone saved on a windowsill for decades.

Colorful Pebbles and Old Tools Hint at Ancient Souvenirs

This is a review paper, meaning the authors pulled together earlier excavations, including their own work in Israel, instead of digging a new site. Researchers who studied the Qesem Cave pebbles suggested the stones may have been valued for their looks, the memories they stirred, or sentiment.

At Sakhnin Valley in Israel’s Lower Galilee, about 10 of more than 200 surveyed stone tools called handaxes were shaped around fossil imprints or odd geological features in the flint. Toolmakers left those quirks where they could be seen and touched, even though such stones were harder to work and were usually avoided. Because the features come from the valley’s fossil-rich rock formations, the authors argue they tie each tool to one specific spot.

Old tools offer a third example. After long stretches outdoors, flint develops a weathered layer called a patina. At sites including Revadim, Jaljulia, and Qesem Cave, someone picked up an old, weathered piece and resharpened only the cutting edge, leaving the weathered surface intact. Wear marks on these tools under magnification show mostly light use afterward, which the authors say fits with keeping the tools as souvenirs rather than heavy cutting or chopping.

Souvenirs May Have Helped Early Humans Trust Their Own Memories

Keepsakes may have helped with a hard job: telling real memories from imagined ones. A pebble or fossil-marked handaxe tied to a particular place could add physical detail that makes a real experience easier to recognize. A keepsake cannot prove a memory is accurate, the authors stress, but it narrows down where the memory could have come from.

Once that habit became routine, the researchers propose, it created what they call a “souvenir niche,” a world where keeping objects was normal. People who were better at combining their own memories with physical objects may have had an edge in tasks that depend on trusted memories, such as tracking alliances, favors owed, and claims to particular places. Because those skills vary between people and are partly inherited, natural selection could have favored them.

A shrinking food supply may explain why the habit took hold. In the region that includes Israel, elephants, a dependable food source, vanished around 400,000 years ago, pushing hunters toward smaller prey and unfamiliar territory. Portable pieces of familiar places may then have become worth keeping, the authors propose, though that link remains untested.

Other Animals Collect Objects, but None Clearly Keep Souvenirs

Plenty of animals collect things, but the paper says none of the known cases match. Wild magpies, famous for supposedly hoarding shiny objects, were found wary of metal objects rather than attracted to them. Crows and their relatives stash food and tools for practical reasons. Captive orangutans and chimpanzees showed interest in odd objects and crystals, but neither study showed apes saving them as reminders of a place or event.

Spotting a true souvenir habit would mean following one animal and one object for months, so it could exist unnoticed.

Three Kinds of Studies Could Test the Souvenir Hypothesis

Several tests could prove the idea wrong. Archaeologists could check whether saved objects cluster near hearths and living spaces instead of only near raw stone supplies. Psychologists could test whether people with personal keepsakes are better at telling where a memory came from than people without them. Developmental researchers could study whether sharing keepsakes between caregivers and young children sharpens a child’s later ability to do the same.

By the authors’ own account, the idea would fall apart if the saved items turned out to be efficient working tools made from local stone, with nothing special about where they came from.

Pebbles with no obvious job, hauled into one cave generation after generation, demand an explanation, and souvenirs are now a testable one. Saving a ticket stub may echo a habit as old as half a million years, one that might even have helped shape the brain doing the remembering. Until archaeologists and psychologists run the tests, that remains a hypothesis, but a specific one that can be proven wrong.

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