I was out on the deck one day last Spring, brushing the dog and catching some rays, and watching the nuthatches take possession of the owl box from a squirrel. It was a quiet day, so when I heard the doves suddenly fly up in alarm one yard over, I looked to see what was up. A hawk had apparently caught one of them. He flew up into a tree, paused for a moment to get a better grip and took off, presumably for his own family's nest with dinner for his mate & nestlings. It seemed significant to me, somehow. There it was, new life beginning for the nuthatches, a life ending for the dove, and maybe for its babies if it already had any at this point, and life, presumably, continuing for the hawk and his family. When one of us dies, it doesn't (usually) contribute to the continuing life of another being--these days, we tend to do that while we're living, with dying for another being the exception rather than the rule. But the other part, the suddenness and the unpredictability, that fits with our experience.
We are here, until we are not. That particular afternoon it could just have easily been the other dove that the hawk caught, or one of the nuthatches. Or the nuthatches could have lost their standoff with the squirrel whose box that has been all winter. Or the dog or I could have been hit by a falling limb. We are here. Until we are not.