{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T03:19:31Z","timestamp":1776395971233,"version":"3.51.2"},"reference-count":62,"publisher":"The Royal Society","issue":"1948","license":[{"start":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:00:00Z","timestamp":1776297600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:00:00Z","timestamp":1776297600000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,4,16]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>When facing disruptive events, such as epidemics, terrorist attacks or financial crises, individuals often exhibit protective behaviours, including mass escape movements and stockpiling essential goods. These collective responses are predominantly driven by a social amplification process, where an initial decision-maker is imitated by others, triggering large-scale behavioural cascades. However, the mechanisms shaping this phenomenon remain unclear. Here, we present an experiment examining the propagation of protective behaviours in dyadic transmissions involving 210 participants. Our research uncovers an asymmetric social response, where individuals tend to copy protective behaviours more strongly than inaction. This pattern causes large amplification cascades in simulated transmission chains and is more pronounced following a brief but intense shock compared to a longer, minor one. Furthermore, our results demonstrate an extended period of collective vigilance post-shock, suggesting that social transmission can facilitate rapid behavioural adjustment during crises. By examining the interplay between individual protective behaviours and group dynamics, our study contributes to a better understanding of how adaptive social responses emerge in uncertain and dynamic environments.<\/jats:p>\n                  <jats:p>This article is part of the theme issue \u2018The evolution of collective intelligence\u2019.<\/jats:p>","DOI":"10.1098\/rstb.2024.0451","type":"journal-article","created":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T08:08:35Z","timestamp":1776326915000},"source":"Crossref","is-referenced-by-count":1,"title":["Asymmetrical social copying drives behavioural cascades following a shock event"],"prefix":"10.1098","volume":"381","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1268-6332","authenticated-orcid":false,"given":"Mehdi","family":"Moussaid","sequence":"first","affiliation":[{"name":"Max Planck Institute for Human Development 1 , ,","place":["Berlin, Germany"],"department":["Center for Adaptive Rationality"]},{"name":"UM6P 2 , ,","place":["Rabat, Morocco"],"department":["School of Collective Intelligence"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8558-8568","authenticated-orcid":false,"given":"Wataru","family":"Toyokawa","sequence":"additional","affiliation":[{"name":"Riken 3 , ,","place":["Wako, Japan, 351-0195"],"department":["Riken Center for Brain Science"]},{"name":"University of Konstanz 4 , , ,","place":["Konstanz, Baden-W\u00fcrttemberg, Germany"],"department":["Department of Psychology"]},{"name":"University of Konstanz 5 , , ,","place":["Konstanz, Baden-W\u00fcrttemberg, Germany"],"department":["Center for the Advanced Study of Collective Behaviour"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3460-0392","authenticated-orcid":false,"given":"Ralf","family":"Kurvers","sequence":"additional","affiliation":[{"name":"Max Planck Institute for Human Development 1 , ,","place":["Berlin, Germany"],"department":["Center for Adaptive Rationality"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"175","published-online":{"date-parts":[[2026,4,16]]},"reference":[{"key":"2026041604081980800_R1","doi-asserted-by":"crossref","first-page":"1337","DOI":"10.1126\/science.1245200","article-title":"The hidden geometry of complex, network-driven contagion phenomena","volume":"342","author":"Brockmann","year":"2013","journal-title":"Science"},{"key":"2026041604081980800_R2","doi-asserted-by":"crossref","first-page":"81","DOI":"10.1126\/science.1205068","article-title":"Pattern in escalations in insurgent and terrorist activity","volume":"333","author":"Johnson","year":"2011","journal-title":"Science"},{"key":"2026041604081980800_R3","doi-asserted-by":"crossref","first-page":"812","DOI":"10.1111\/risa.12654","article-title":"Evacuation from natural disasters: a systematic review of the literature","volume":"37","author":"Thompson","year":"2017","journal-title":"Risk Anal."},{"key":"2026041604081980800_R4","doi-asserted-by":"crossref","first-page":"735","DOI":"10.1007\/s10955-014-1024-9","article-title":"Saving human lives: what complexity science and information systems can contribute","volume":"158","author":"Helbing","year":"2015","journal-title":"J. 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