January
9, 2019 by Bob Yirka, Phys.org report
A team of
researchers with members affiliated with the University of Auckland, the
University of Cambridge, Bertha von Suttner University and the Max Planck
Institute for the Science of Human History has found evidence that suggests New
Caledonian crows can infer the weight of an object by watching how it behaves
in the wind. In their paper published in Proceedings of the Royal Society
B, the group describes experiments they carried out with crows they captured
and what they found.
Humans
can easily gauge the weight of objects by their behavior under windy conditions.
In breezy conditions, a napkin will fly off a table at an outdoor café, for
example, but a fork generally will not. We prepare for this eventuality by
placing something heavy on the napkin, but not on the fork. But until now, no
other creature has been found to have this ability.
To find
out if New Caledonian crows might have this ability, the researchers went out
into the wild and captured 12 specimens and brought them back to their lab. All
of the birds were taught to use the weight of an object as the
criteria needed in order to receive a food reward. Half were taught that
the lighter of two objects was needed, while the other half were taught that it
was the heavier object that was needed to get their reward.
