Thesis #24 – Altering all cell-molecular regulatory signaling during the aging phase will provide at most partial amelioration for the problem of declining adaptation, because dysfunctional signaling will also arise at organ and systemic levels as a result of the de-tuning of adaptation with age.
The functioning of a whole organism as complex as a human involves much more than the repetitious execution of the same processes over and over again. Rather, our physiology involves a number of signaling pathways among tissues and organs, from the slower hormonal signals to the rapid electrical signal transmission carried out by neurological tissue.
At the peak of adaptation, just prior to the onset of reproduction in an evolving population, this coordination of function by signaling is amazingly proficient. Thus we have the thirteen year-olds with an amazing ability to acquire random new information, whether from friends, the internet, or even their teachers. But with an evolutionary view of health and function like the present one, these gifts are the predictable effect of natural selection operating at full power.
Conversely, as the forces of natural selection fade with adult age, our mental facility and our physiological responsiveness deteriorate. This deterioration is masked in humans by the accumulated intellectual capital and skills that we have acquired thanks to our earlier proficiency at signaling, coordination of functions, and marshalling of resources. Older professors usually know more than beginning graduate students, and veteran athletes know the tricks of the game that the upcoming rookies are just learning. But the reaction times of the professors and the veteran athletes will generally be slower than those of their younger colleagues.
It is not the case that, during aging, a perfectly attuned organism progressively loses function solely because of a substratum of progressively damaged cells or organs. In addition to any such damage, the evolutionary genetic tuning required to sustain the signaling systems of the human body will not be there at later ages. Again, it is not just that the car is rusting; the driver is also falling asleep. To suppose otherwise requires a resort to a Cartesian dualism in which “the mind” and other coordination functions come from another realm, one that is not subject to the lack of information that afflicts the body, considered as an inert aggregate of cells. And I reject any such Cartesian dualism, as I suppose most modern biologists must.
Thus, whatever damage we are able to repair at the level of cell or organ, there will still be failures of function arising from progressively more severe failures of coordination among tissues and organs. Perhaps a useful metaphor for this would the American Congress, which features a lack of coordination that can boggle the mind of the uninformed American voter or the visitor from a country that has a rational legislative system, particularly one not designed to thwart cogent and expeditious policy.