The little bird on the left is recalling his mother, bringing him food, and appearing here as a ghostly figure on the right. His migration flight has likely taken him far away, as he watched the world from high in the sky, while the world watches him. It's the same with us. We get busy living our lives and then as we get older, we come to a point where we think back and contemplate our own origins, as if it were something we just forgot to think about for a time.