Why and how crows have colonised the world?
Humans, crocodiles and crows have something in common. They have all spread to every corner of the planet. If we travel from Barcelona to Australia, in spite of the enormous distance, we will find groups of animals that also live in our home, we will see for example owls, swallows, turkeys, crows and certainly humans, all these animals are so far away because they have been able to colonise the planet almost entirely. But what is it that they have been able to do so while other animal groups have been reduced to small areas of the planet?