New Caledonian crows can infer weight

https://indianapublicmedia.org/amomentofscience/new-caledonian-crows-can-infer-weight.php

New Caledonian crows can infer weight

By RORY BOOTHE
Posted July 25, 2024

(Audio at link)

This ability to represent weight to ourselves as a cause for what we see in the world has long been considered an exclusively human mental activity. (NAPARAZZI / flickr)

If you see an object blowing down the street, you will infer that it is light. That will be your conclusion even if you can’t determine what the object is.

This ability to represent weight to ourselves as a cause for what we see in the world has long been considered an exclusively human mental activity. Not even chimpanzees have shown the aptitude.

But lo, a bird swoops down to make some observations. It’s a member of the crow family, the corvids, and it can infer weight like humans. It’s the New Caledonian Crow, which resides on its namesake island in the Pacific Ocean.

In 2017, researchers from various international universities observed twelve New Caledonian birds. In the lab, the crows learned to drop an object into a tube based on the object’s weight to receive a food reward. Then, six crows were taught that only light objects got them a treat; the other six only received treats for transferring heavy objects.

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