Study
Social learning spreads knowledge about dangerous humans among American crows
Cornell, Heather N.; Marzluff, John M.; Pecoraro, Shannon
Proceedings of the Royal Society B: Biological Sciences, 2012
Building on the mask experiment, the team tracked how the scolding response to a "dangerous" mask changed over five years across several sites, and compared birds that had been trapped themselves with birds that had only seen others react.
- Studied in
- Corvus brachyrhynchos
- Sample size
- 5 study sites tracked over five years
The proportion of crows scolding the dangerous mask increased over time and spread well beyond the birds originally caught, including to juveniles that could not have been present at the trapping.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Knowledge about a specific dangerous human is transmitted socially — horizontally between adults and vertically from parents to offspring.
How NatureHQ reads it
This turns a memory result into a cultural one. The interesting part is not that a crow remembers a face, it is that a face can become a piece of shared information in a crow population, held by birds with no personal experience of the event. It is a small, well-evidenced example of social transmission in a wild bird.
- Transmission was inferred from the spread of the response, not observed directly bird by bird.
- Individual identity of most responding birds was unknown, so repeat scolders could inflate counts.
- Confined to American crows in an urban and suburban setting in one region.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: The Royal SocietyPublished by the Royal Society.
doi.org/10.1098/rspb.2011.0957
This reference was resolved automatically against Crossref and OpenAlex on 2026-08-11.
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