A new study argues that an asteroid belt similar to the one in our solar system is essential to the development of life on rocky planets inside the belt because asteroids will sometimes smash into those eocky worlds, bringing water and organic compounds-- the essentials of life. The study further suggests, based on evidence so far obtained, that such asteroid belts are rare.
It's the latest in a string of studies that say, in effect, life similar to that on Earth needs situations similar to those that have existed in, on, and around Earth. Yes, the arguments mustered are sound enough, but there's the barest hint of desperation in the whole approach. It seems to want to insist we are the product of a special sequence of cosmic events. Trying to broaden our understanding of life and how it might come to be might be more useful.