What´s TRUE on that?!
In one of the Aesop´s fables we can find story about crow, which found in hot, sunny weather jug with water. Crow tried to drink it, but water was on the bottom and crow had too short beak. Crow knew, that if she will break the jug, she will lose water. Crow took stones and started to throw them into the jug. As in the jug were more stones, the water level gradually lifted and after moment crow could drink it.
This story is telling us about intelligence of crows. Maybe for some of us are not crows one of the most intelligent from birds or animals, but these black birds are more clever than can be seen from the first sight. In fact, crows are one of the most intelligent birds. Of course, should be mentioned also, that, there are more than 40 species, so not all of the crows are smart like that. But most smart of them has intelligence of 6-7 year old child. They have even big brains when we compared them to their body size.
Usually you can see crows even in the city, where they are dropping down to the road or pavement nuts from big highs to open the nuts. However, crows can handle this problem even in cities, where there are not enough high places and such tall buildings. In these cases, they are waiting on pedestrian on the red. When cars start to go, they throw a nut under their wheels and the nut will get open.
With crows were even done experiments, how smart they are. Scientists even repeated the case from the fable, where the crows were really throwing stones to get to the water. Another of the tests was, that to crows were showed geometrical shape, when only under that one was food. When it was clear that they can prove the shape, the test get more difficult. Patters were shown with different size, relation, etc.
Different experiments and tests showed, that crows can different problems solving intuitively. It means, that the problem and situation can solve without any explanation, eg. With twig they can pulled out from the trees caterpillars. They are even bending twigs to get at their end hook.
Thus, crow is truly intelligent bird, which can surprise us even in the future by its powers and knowledge. Therefore, it is not surprising that Aesop has proven it to be an intelligent creature, which can get to the water in jug.