2023-12-18 カリフォルニア大学バークレー校(UCB)
◆研究は、ボノボとチンパンジーが、以前に1年以上一緒に生活していた仲間の画像に注視することから、ある程度の認識がある可能性を示しています。この発見は、人間、チンパンジー、ボノボの長期記憶が、約600万年から900万年前に存在した共通の祖先に由来する可能性が高いとする理論を補強しています。
◆研究はまた、長期記憶に関する以前の知見を広げ、進化生物学と心理学に関連する重要な質問を提起しています。これには、なぜ人間は優れた長期記憶を発展させたのかという問いも含まれています。
<関連情報>
- https://news.berkeley.edu/2023/12/18/move-over-dolphins-chimps-and-bonobos-can-recognize-long-lost-friends-and-family-for-decades
- https://www.pnas.org/doi/full/10.1073/pnas.2304903120
ボノボとチンパンジーは何十年もの間、見慣れた同胞を記憶している Bonobos and chimpanzees remember familiar conspecifics for decades
Laura S. Lewis , Erin G. Wessling, Fumihiro Kano , Jeroen M. G. Stevens
Proceedings of the National Academy of Sciences
DOI:https://doi.org/10.1073/pnas.2304903120
Significance
While human social memory lasts decades and tracks relationships, less is known about nonhuman ape long-term memory.We present evidence that both chimpanzees and bonobos recognize the faces of familiar conspecifics even after many years of separation. An eye-tracking task revealed that apes’ attention was biased toward former groupmates over strangers, and this pattern may persist for at least 26 y beyond separation. Apes’ memory may also represent the quality of their social relationships: Apes looked longer toward individuals with whom they had more positive relationships.Thus, critical properties of human memory may reflect deep homologies with other apes, likely providing the foundation for the emergence of complex cooperative relationships that operate across long time-scales.
Abstract
Recognition and memory of familiar conspecifics provides the foundation for complex sociality and is vital to navigating an unpredictable social world [Tibbetts and Dale, Trends Ecol. Evol. 22, 529–537 (2007)]. Human social memory incorporates content about interactions and relationships and can last for decades [Sherry and Schacter, Psychol. Rev. 94, 439–454 (1987)]. Long-term social memory likely played a key role throughout human evolution, as our ancestors increasingly built relationships that operated across distant space and time [Malone et al., Int. J. Primatol. 33, 1251–1277 (2012)]. Although individual recognition is widespread among animals and sometimes lasts for years, little is known about social memory in nonhuman apes and the shared evolutionary foundations of human social memory. In a preferential-looking eye-tracking task, we presented chimpanzees and bonobos (N = 26) with side-by-side images of a previous groupmate and a conspecific stranger of the same sex. Apes’ attention was biased toward former groupmates, indicating long-term memory for past social partners. The strength of biases toward former groupmates was not impacted by the duration apart, and our results suggest that recognition may persist for at least 26 y beyond separation. We also found significant but weak evidence that, like humans, apes may remember the quality or content of these past relationships: apes’ looking biases were stronger for individuals with whom they had more positive histories of social interaction. Long-lasting social memory likely provided key foundations for the evolution of human culture and sociality as they extended across time, space, and group boundaries.
