As the body of human knowledge grew over the ages, and as the social and cultural life of our species became more complex, the value of older adults increased as well.
This is why natural selection has favored a relatively long human life span despite the fact that the female reproductive potential typically ends in the late forties.
Clearly, when it comes to human beings, the capacities to teach, to transmit wisdom and skills, and to serve as a repository for the culture are just as important as the capacity to reproduce. The complexity of today’s global society and the variety of skills required to master those complexities only amplify the importance of the older adults among us.
~ Gene D. Cohen, M.D., Ph.D.