Parental efforts are, at times directed toward the offspring that will best promote their fitness. The offspring that are the less profitable option become good elicitors of parental investment. A deeper parental allocation problem is the cost-benefit relationship between parental investment and other fitness promoting activities. For instance, pursuing multiple sexual partners. As parents age, their reproductive value declines, exponentially altering future decision making.
Parents continue to accept greater risk as their own reproductive value declines.
Measuring reproductive value decline in parents has been far more difficult than the increase with their offspring. The more risk parents accept has many other causes besides a decline in their own reproductive value. Human females generally show a decrease with age, as their potential reproductive life span ends, in devaluation of young. The variables relevant to changes in maternal solicitude are expected to be similar for fathers. But females' alternative reproductive efforts decline more rapidly than men since their reproductive value declines much earlier than males reproductive value.