The problem is that, historically, from a biological point of view, evolution was not on our side to live so long. We need to recall that biological evolution took place in an era of scarcity. In primordial times, there were a limited number of calories to go around for our ancient predecessors. Since older individuals in the community were simply competing for the limited food and other resources available, it was not in the best interest for the survival of the tribe or community to allow its elderly to remain alive too long. There was a survival advantage to a community whose members remained alive and healthy (just) long enough to reproduce and raise their children; but then it would be best if ‘‘aging genes’’ were to express themselves and cause adults to age rapidly, essentially to shrivel up and blow away. A community whose individuals didn’t survive much beyond the time their offspring were selfsufficient would possess a natural selection advantage over a community where the members lived into ripeold age (and decrepitude). In the first community, it is more likely that the younger members would have a greater chance of surviving because of less competition for scarce calories and these would be genes increasing survival advantage. It is important to realize that our DNA really hasn’t changed very much in the past 100,000 years or so. These ‘‘aging genes’’ remains key letters in the genetic alphabet soup in which we still swim today. But, in modern times, the conditions that selected for these genes in millennia past no longer apply. Today we live in an era of abundance. Granted, many people still live under conditions where there isn’t enough food to go around, and a significant portion of human kind still lives precariously close to starvation, but this reflects political and social issues more than lack of technological capability. If allowed, technology could easily solve the problem of inadequate food for all peoples of the world.4 So, technology has allowed us to override this remnant of our biological heritage, and, there is no longer a survival advantage to short-lived humans.
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