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Causal understanding of water displacement by a crow

PLOS Media
Demos
YouTube
3 HN users recommended this demo3 months2015–2023 score 3
Years with an HN recommendation, 2007–2026

Used as vivid evidence of crow intelligence and animal physical reasoning in discussions of cognition.

A silent PLOS ONE video of New Caledonian crows solving Aesop's Fable puzzles by dropping objects to raise water and reach food. It shows example trials from experiments testing causal understanding of water displacement.

“This video is a startling verification.of the crows mental capabilities.” (HN, 2020)

3 recommendations · 8 citations · Demos

11 Hacker News comments

From the HN archive; up to 20 kept per video, favoring different commenters. Recommendations first.

@lr4444lr Mar 2016 Recommends
on HN thread Why Neuroscientists Need to Study the Crow
The reasoning ability and executive function of birds, crows in particular, is astonishing. Intelligence (certain kinds, at least) may be just as reliant on brain:body mass ratio as it is on overall brain size and complexity. [link] [this video]
Crow demonstrating reasoning by raising water level to reach food.
@danmostudco Dec 2019 Recommends
on HN thread Crows could be the smartest animal other than primates
Crows are astoundingly intelligent. If you're having a slow day, a quick youtube of "crows solving puzzles" yields some great videos of them solving complicated tasks like water displacement to reach food[0]. I believe raccoons share this achievement. Additionally, there was a thread on here some time ago[1] by a Dutch Startup[2] about trying to teach crows to exchange cigarette butts for treats inside a tiny device place in parks, I always thought that was a funny idea if you could get the crows to teach one another. [0] [this video] [1] [link] [2] [link]
Crow solving water displacement puzzle to reach food.

Citations, criticism and jokes

@acqq Aug 2015 Cites it
on HN thread A new Stephen Hawking presentation about black holes
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When you formulate it so, the problem is the question itself, as, except if we are religious believers, we don't have any reason to consider a "soul" (or a "consciousness") to be a "nonphysical entity." Look at the etymology of the "psyche:" it's "the breath." At the time people explained their environment unscientifically they considered that the existence of "breath" makes the difference between the dead and the living person but also between the conscious and the unconscious bodies. Animals do breathe too. But humans saw themselves as "special" in their religious setup. As a kid would ask "does my dog go to heaven too when he dies?" See, we go deeper and deeper in religious explanations which just postulate something non-existing (once you accept nonphysical soul, it's easier to believe in heaven or reincarnation or whatever). Now go back and ask, if you believe that the only thing we can "see" around us that doesn't have the "physical entity" is the "soul" of humans why do you do so? Are humans by any way "the chosen ones" in the animal world, looking at their physical bodies and the processes in them? The scientific view doesn't see them so. The human "consciousness" is, so observed, more complex than the "consciousness" of the crow on the lawn due to the more complex brain, but both of these can be explained as the function of their physical "hardware" (the body and the brain) and the interaction with the environment. The "consciousness" as a "neurological process by wh
@throwawaymath Aug 2018 Cites it
on HN thread 'Intelligent' crows to pick up litter at French theme park
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> I read somewhere about training crows to pickup cigarette butts in exchange food. I’ve always wondered if it would be possible to train a crow to pick up loose coins for food. Probably not. It probably seems like I'm shilling this researcher's blog in this thread at this point but this commentary [1] gives a short explanation of why. One of my hobbies is actually bird watching, particularly with crows. I love the animals, they're very fascinating creatures. I've had the opportunity to interact with many of them because I set out peanuts for them near my neighborhood. They've very gradually become acclimated to this routine, and they reliably arrive to pick up food if I make a particular noise and they're in the area. But I'm very skeptical that I could "train" them to start exchanging items for food. In captivity a crow's intelligence can be especially fostered and trained because there's no other source of food to distract it. If you want it to proceed through a puzzle [2] to get food it has to do so. But wild crows are very, very cautious and (like most animals) very economically rational in their feeding habits. To date none of the wild crows who give people items have been trained to do so, it's been a happy accident (it's never happened to me, unfortunately). If you start imposing an exchange system on the food dispensary, you might find that the crows simply go elsewhere for easier meals. _____________ 1. I read somewhere about training crows to pickup cigarette butts
@gus_massa Dec 2019 Cites it
on HN thread Ask HN: Do animals grasp the concept of solid-liquid-gas?
It's a very interesting question. I guess big apes can, but I have no proof at all. Also, the extension of the question to the ice-water transition in the other comment is interesting too. Anyway, the first thing that came to me mind was " Causal understanding of water displacement by a crow " [this video]
Crow understanding water displacement as evidence of animal physical reasoning.
@Stratoscope Jan 2023 Cites it
on HN thread Causal understanding of water displacement by a crow (video, silent, 2014)
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Video also available on YouTube (possibly with ads): [this video] Paper available here: [link] "Using the Aesop's Fable Paradigm to Investigate Causal Understanding of Water Displacement by New Caledonian Crows" Abstract: Understanding causal regularities in the world is a key feature of human cognition. However, the extent to which non-human animals are capable of causal understanding is not well understood. Here, we used the Aesop's fable paradigm – in which subjects drop stones into water to raise the water level and obtain an out of reach reward – to assess New Caledonian crows' causal understanding of water displacement. We found that crows preferentially dropped stones into a water-filled tube instead of a sand-filled tube; they dropped sinking objects rather than floating objects; solid objects rather than hollow objects, and they dropped objects into a tube with a high water level rather than a low one. However, they failed two more challenging tasks which required them to attend to the width of the tube, and to counter-intuitive causal cues in a U-shaped apparatus. Our results indicate that New Caledonian crows possess a sophisticated, but incomplete, understanding of the causal properties of displacement, rivalling that of 5–7 year old children.
YouTube copy of the silent crow video, with paper abstract.
@squarefoot Jul 2023 Cites it
on HN thread She Steals Surfboards by the Seashore. She’s a Sea Otter
Some animals learn to use tools to solve problems, for example crows [0]. What if that otter was just using the board to travel longer distances (=> finding more food) by keeping nearby a safer place to rest on? 0: [this video]
Example of crows using tools to solve problems.

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