This episode takes us into a particular dimension of the world in which we live, that of large concentrations of life and living beings: animals, men, and even cells. Let's see when and why they aggregate, act, but, above all, move en masse. With spectacular images from the BBC we enter the formidable world of small insects, birds, fish up to the large mammals of the savannah. In nature, the winning strategy for escaping predators seems to be that of the group. And this was exactly the secret of the Roman legions. The barbarians were used to fighting individually, even though they moved en masse. In front, however, there were soldiers fighting in groups, well aligned, with the various units of the legions moving as if in a game of chess. We will explain to you the secrets of the Roman war machine. We follow the flocks of birds in their periodic migrations.
