"The Evolution of Immortality"

Evolution, in general, is not "nice" to individuals. It works by killing off the unfit and the unlucky.

The reason immortality has not arisen in individuals is because individual immortality is not important for the survival and health of a whole population.

In fact, there are two reasons immortality CAN'T be selected for:

1. Having the parent generation survive forever would work against evolution since the parents would be competing with their own offspring. The parent generation would (because of their greater experience) have an advantage over their own offspring. In populations with a lot of competition for resources, the offspring would be the least fit (even if their genes were better).

2. A second reason immortality is not selected for is that selection occurs early in an individual's life cycle.

The individuals who are the ancestors of the present generation are those who survive childhood, reproduce, and then live long enough to insure their offspring's survival to reproduce. What happens after that CAN'T be selected for since the selection (before and during reproduction) has already occured.

There is no way for selection to detect if one individual is more likely than another to get cancer in their sixties.

So as great as immortality sounds, evolution on its own won't do it. We will have to help a bit with some biotechnology.

This original document can be viewed on AskMe.com.