It is the very nature of the human condition to survive. To live. To even outlive the next guy (or gal, and for the purposes of this post, all references to "man" also include women). Man is afraid of dying out and being forgotten. Why else do you think that there are so many recorded instances of human existence? Whether it's from cave drawings or published accounts of human triumph, man has made sure that the future generations know that the first humans did, in fact, exist. For that matter of survival, this is exactly why man goes to war- to outlive everyone. Modern medicine is also a way of postponing physical death. In that time that the medicated are living, they are busy making sure that everyone who physically outlives them remembers those that came before them. Oral accounts of some great ancestor ensure that a memory of someone lives on. That ancestor may not have been president or found the cure for cancer, but that spaghetti recipe has transcended generations, and for that, the creator of said recipe has achieved immortality.
Immortality is the name of the game of life, folks. Memory is the strongest sense we have to the past and the act of remembering someone ensures that the deceased live on. They survive by mere memory and recollection. Darwin had it right the first time: Survival of the fittest, if not the fittest memory.