What would a world be like without spring? During this time of year, nature awakens with an unstoppable rhythm of love, birth and flowers. But let's try to think for a moment if we find ourselves in a world without spring: a hypothesis that is obviously unrealistic, but which highlights the importance of this time of year in our ecosystem.

And no, it's not just a fantasy, but a reality that emerges from scientific research on climate change. But before we can understand what the consequences of the absence of intermediate seasons could be, a prerequisite is needed: spring only exists in mid-latitudes. While from an astronomical point of view it is determined by the position of the Earth in its orbit around the Sun, from a meteorological point of view it is an annual cycle of temperatures that marks the transition from cold to increasingly warmer temperatures. (Marco Caccianiga, professor of botany at the University of Milan, more at www.lasvolta.it)