h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I'd like to step back and provide a little corrolary to the assumption that an allele that causes death after reproduction will not be selected out of the population.

In the case of animals who raise their young to a certain age, an allele that causes death anytime before the child is fully grown might be selected against. If the adult parent dies, the child that possibly carries the same gene may also starve or otherwise die.

This is more complex in the case of animals where adults may adopt and raise young that are not their own. In such a case, natural selection is sidestepped somewhat.

To add even greater complexity, there is an argument that tribal human cultures tended to benefit from extended memories of very old members. For example, they might remember how some members of the tribe survived the last great famine two generations ago. So tribes with fewer alleles causing death past reproduction might have survived better as a group.

In general, I would agree that human civilization has had the interesting benefit of increasing our lifespans. As the complexity of our society grows, the averate amount of education needed to sustain it also grows. The longer we spend in school, the later we start families.

what is life? Life doesnot die. every species has a different life span Ageing is a natural process like growing up Death can come at any stage at any time Attitudes can definitely change personalities If one tries to be at peace in harmony with his atmosphere he can check diseases consequently ageing slows down and natural life increases and death a finality becomes part of completing and finishing chapter