Homo Memorabiliaxis: Souvenirs and the Evolution of Autobiographical Memory and Self.

Humans routinely keep souvenirs objects retained for the memories they evoke, yet the evolutionary and cognitive consequences of mnemonic collecting remain unclear. Existing discussions of curated objects concentrate on later prehistory and modern humans and view such objects at the social level, as carriers of shared cultural meaning or as markers of status. Here, we address an earlier time period and locate the phenomenon at the personal rather than the social level. By integrating archaeology with theories of extended memory and niche construction, we synthesize evidence consistent with systematic curation of items beyond purely utilitarian needs from the terminal Lower Palaeolithic (~500 kya) onward, including transported distinctive stones, fossils, and the prolonged retention of patinated "old" stone tools whose earlier surfaces were deliberately preserved. We propose that curated keepsakes functioned as portable external memory devices. Beyond cueing recall, they may have helped authenticate self-relevant past events by providing durable material traces that support source monitoring-distinguishing experienced from imagined events. As such practices became routine, they could have created a "souvenir niche" in which individuals who better integrated internal recollection with external tokens gained fitness benefits. The token's reference is personal, but its consequences can be social, supporting tasks like tracking alliances, reciprocity, and place-based obligations. These benefits may have strengthened selection on neural systems facilitating the development of autobiographical memory and sense of self via gene-culture coevolution. We outline archaeological, developmental, and experimental predictions that distinguish this mnemonic-authentication account from aesthetic or economic explanations and suggest approaches for testing them. Viewing curated objects as memory technology links early material culture to the evolutionary shaping of human autobiographical memory.