Study
Do New Caledonian crows solve physical problems through causal reasoning?
Taylor, Alex H.; Hunt, Gavin R.; Medina, Felipe S.; Gray, Russell D.
Proceedings of the Royal Society B: Biological Sciences, 2009
Crows faced a trap-tube task and variants of it in which the visual features of the apparatus were changed while the causal structure was held constant, and vice versa, separating a rule about appearance from a rule about how things work.
- Studied in
- Corvus moneduloides
- Sample size
- 6 wild-caught New Caledonian crows
Crows that had learned to avoid the trap transferred correctly to versions that looked different but worked the same way, and failed on versions that looked the same but worked differently — but performance was inconsistent across individuals and tasks.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
The crows’ performance is consistent with reasoning about causal structure rather than about surface features, though not uniformly so.
How NatureHQ reads it
The transfer design is the whole point, and it is the standard NatureHQ applies to any claim of animal understanding: an animal that has learned "avoid the hole" and an animal that has grasped "objects fall through holes" behave identically until you change the apparatus. That said, the honest reading here is mixed. Some birds transferred and some did not, and six wild-caught individuals is a small base for a claim about a species.
- Six individuals with inconsistent performance between them.
- Trap-tube tasks have a long history of alternative low-level explanations.
- New Caledonian crows are exceptional even among corvids; this does not describe crows generally.
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.2008.1107
This reference was resolved automatically against Crossref on 2026-08-11.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-08-09.