ArticleProceedings. Biological sciences2019
New Caledonian crows infer the weight of objects from observing their movements in a breeze.
Article in Proceedings. Biological sciences, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 9 papers.
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Who cites it
9 citing papers in PubMed.
- A special issue in honor of the contributions of Professor Nicola S. Clayton FRS.Learning & behavior · 2025Article
- Testing weight-based conditional discrimination in Goffin's cockatoos, Cacatua goffiniana.PloS one · 2025Article
- Do kea parrots infer the weight of objects from their movement in a breeze?Biology letters · 2024Article
- Hooded crows (Corvus cornix) manufacture objects relative to a mental template.Animal cognition · 2024Article
- Goffin's cockatoos discriminate objects based on weight alone.Biology letters · 2021Article
- Animal cognition in an urbanised world.Frontiers in ecology and evolution · 2021Article
- Neural Processes Underlying Tool Use in Humans, Macaques, and Corvids.Frontiers in psychology · 2020Review
- Macphail's Null Hypothesis of Vertebrate Intelligence: Insights From Avian Cognition.Frontiers in psychology · 2020Review
- Delayed gratification in New Caledonian crows and young children: influence of reward type and visibility.Animal cognition · 2020Article
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Authors and funding
8 authors.
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Abstract
Humans use a variety of cues to infer an object's weight, including how easily objects can be moved. For example, if we observe an object being blown down the street by the wind, we can infer that it is light. Here, we tested whether New Caledonian crows make this type of inference. After training that only one type of object (either light or heavy) was rewarded when dropped into a food dispenser, birds observed pairs of novel objects (one light and one heavy) suspended from strings in front of an electric fan. The fan was either on-creating a breeze which buffeted the light, but not the heavy, object-or off, leaving both objects stationary. In subsequent test trials, birds could drop one, or both, of the novel objects into the food dispenser. Despite having no opportunity to handle these objects prior to testing, birds touched the correct object (light or heavy) first in 73% of experimental trials, and were at chance in control trials. Our results suggest that birds used pre-existing knowledge about the behaviour exhibited by differently weighted objects in the wind to infer their weight, using this information to guide their choices.
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