Aging and obesity research share an outlook that is misguided.

Aging researchers are looking for the clock that times the onset of
the aging process.  This reminds me of the time that brain
researchers were looking for the command neuron in the brain that
ran everything.  It is an error that comes from what I call the
centralized mind set; the coordination of processes that appear to
be complex is attributed to a central commander.  Nothing real and
adaptive, like a human being, works that way (think of it as the
Soviet model of the organism).

There are many clocks in the human organism: the glucose clock, the
unwinding of peptides, the deterioration of the telemeres, the
pulses of the calcium gradients over the cell membranes, the tidal
rhythms in the lungs, the heart beat.  All these clocks are
self-organized and lack any central control.  They work the way they
do because that is the way things are--the chemistry and the
dynamics make it happen, no mysterical force or guidance does it.

All these clocks that have been tracked exhibit chaotic dynamics;
their basins of atraction are not fixed points, or even limit cycles
but strange attractors.  The clock beat (or return time on the
attractor) pulses with the rhythm of natural systems which is
described by power laws.  Such laws, where intensity is distributed
over frequency as 1/f, are the intrinsic dynamics of all natural
systems that have been studied in enough detail to make the
determination.  Our mail list shows the same kind of behavior,
bursts of activity and periods of stasis without characteristic
scale; we share the statistical distribution of earthquakes and
stock market price changes.

The signature of chaos and adaptive dynamic systems is a mixing of
many time and event scales.  This is precisely the situation in the
human organism.  There is no single clock.  What makes us tick is
the mixing of millions of clocks, each running on their own
attractors and pulsing at power law variations.  The search for an
aging clock is doomed and misconceived.

The real issue is how all these clocks are coordinated.  I suspect
that cyclic amp, the ubiquitous second messenger hormone is at work,
among many other coordinating mechanisms.  That is how slime mold
organisms become coordinated---a glucose crisis triggers a camp
release which coordinates aggregation.  From then on, the aging of
the organism follows a definite sequence.

A similar argument can be made for the fat set point (the idea
confuses a basin of attraction with a point, ignores how you move
out of a basin, fails to specify how the set point is set, and
neglects that a set point is not evolutionarily elegant in design),
but I have used up my space.

Arthur De Vany
Professor
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