Crows were the first animals with this ability.
Previous experiments that have been conducted on animals, primarily chimpanzees, showed that despite the ability to sort objects according to weight, they can not determine their weight only based on the observations. Now, researchers have conducted experiments with the participation of 12 ravens, which was caught in the wild.
The crows were divided into two groups and trained to use objects to obtain food. In them were heavy and light items: half Raven hit a heavy object in a tube would receive treats, in contrast to lighter objects, and for the other half of the meal was brought, on the contrary, the use of lightweight objects.
In the next stage, new items that the birds had not seen before, was suspended in front of a fan. Then birds had to observe the objects in two conditions: when the fan in which a lighter object has succumbed to the wind and with the fan off, in which both objects remain stationary. For three days the bird has shown this process every few hours. Finally, crows were tested. The researchers wanted to see whether the birds remember which objects (heavy or light) they should be placed in the tube to obtain the treat. Crows successfully coped with this task.
© 2019, z-news.link. All rights reserved.