this is true.
and the way we know evolutionary biology to work right now is that the age at which species reproduce is what decides the genes that survive.
this is important. this means that stuff that kills you after the age of reproduction decides what genes will improve upon.
so if you're a fan of evolutionary biology, you should probably have six to ten kids when you're 80 if you live that long.
at a certain point, like snakes got limbs, and humans found redheads, we will select out the genes that kill us.