Story : In this episode, an interesting BBC documentary on the Ganges River. Descending from the glaciers of the Himalayas, it crosses much of India until it flows into the Bay of Bengal, the largest in the world. Its path is a treatise on natural history: following it you cross climates, landscapes, ecosystems populated by a great variety of vegetation and animals. But it is also, and above all, a river linked to the great Hindu religion, which considers its waters sacred. Next - in the report by Barbara Gallavotti and Federica Calvia - we will talk about puberty which, in the life of a woman, marks a very important turning point: it makes her capable of bearing children. In the women's watch, the hands, in recent decades, have gone back as much as five years. Why? And with what consequences? Another topic is Nature, a precious source of inspiration for creating the materials of the future.