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The next questions...

Posted by aacohen on 23 Oct 2007 at 19:08 GMT

This is a nice paper and makes an important point. Still, there are several questions it cannot answer:

1) Why doesn't the age of menopause increase to parallel male lifespan? I.e., the cost or trade-offs involved must be different for the reproductive aging and somatic aging.

2) Why do female mammals live longer than males?

3) In the other species with the clearest female post-reproductive lifespan, Short-finned Pilot Whales, the oldest fertile female observed was 39, the oldest living female was 63, and the oldest living male was 43, so for this species it seems impossible that a similar explanation could apply. Why the differences?

I have no answers to these questions at the moment, but believe that we must understand the physiology of reproductive and somatic aging in order to address them. For example, there is still no good explanation for why most oocytes are produced before birth in most mammals - it is the decline in these oocytes that results in female reproductive aging.