Four Cells In A Cockroach : Syston Pacemakers and Halflives [MT118]
David Noel
<davidn@aoi.com.au>
Ben Franklin Centre for Theoretical Research
PO Box 27, Subiaco, WA 6008, Australia.
An organism's response to an external stimulus varies critically with the phase of the
rhythmic cycle that it happens to be in at the time
-- Ritchie R Ward
Living Clocks
In his fascinating book The Living Clocks, Ritchie Ward [Reference 23] tells of the researches of
the Cambridge scientist Dr Janet Harker on cockroaches.
Cockroaches, the most primitive of all creatures which possess wings, are perhaps a long
way removed from humans. But they have organizational simplicity, and functions which
may depend on a complex interaction of organs in higher animals may be much more localized
in such a simple creature. So they can form a good starting point in researches about such
functions.
The area which Janet Harker was researching was that of time senses in animals. Every
living creature possesses some sort of 'time sense', and often a complete range of different
senses for different periods. These time periods range down from decades, as in the Talipot
Palm of Sri Lanka which may wait 60 years to flower for the first and only time, down to
fractions of a second, as in the recharge cycle in animal vision.
Underlying each of these periods or cycle times is some sort of clock mechanism. One of
the most important cycles in life processes is the diurnal rhythm, that dependent on the
alternation of day and night.
Obviously many of these clock mechanisms are dependent on external signals, on what we
might call pacemakers. With the diurnal cycle, the main pacemaker is the rising and setting of the sun. But that is not the whole story.
Most creatures have their own internal pacemakers as well. That is why jet-lag occurs in
people who rapidly fly between different time-zones -- there is a conflict between their
internal and external pacemakers. And this may be the reason why so many people dislike
the practice of altering local time twice each year with 'daylight saving'.
A number of interesting studies have been done of people isolated in deep caverns, well
out of contact with sunlight and external time indicators, but with lighting and such under their
own control. Invariably such people settle down to a quite precise 'day' of their own,
maintaining their day-length fixed within a few minutes, purely from their own internal
pacemakers.
So far I have not seen a convincing explanation of why these 'private' day-lengths vary
from the usual 24 hours, because vary they do. Different creatures -- plants as well as animals
-- may adopt or adapt to private day-lengths varying by as much as an hour or more from the
norm. Of course this is not a large variation, only 5%.
The important thing is that it is clearly evident that creatures do possess accurate internal
pacemakers. Many people are able to wake up each morning at a given time, without the
benefit of an alarm clock. Some can even set an 'alarm clock' inside their heads to wake at
a particular time the next morning -- I can sometimes do this myself. The fact that the
pacemakers involved are really internal ones (and not due, say, to an unexplained ability to
'sense' the position of the sun even though underground) is shown by the fact that the 'private'
day-lengths do not match the ordinary 24-hour one.
Other Life Time-Cycles
Many other time-cycles are very important to life. The heart pacemakers used in people
with irregular heart rhythms are, presumably, only a manufactured substitute for a natural
function which is not performing well -- somewhere inside each animal is a 'circuit' which
generates the next heart-pulse.
Longer-term cycles may concern reproduction. The fertility/ menstrual cycles in women
are, of course, paced externally by the movement of the moon, as well as internal clocks.
Poinsettias can be made to flower out of season by altering their applied day-length --
flowering and fruiting behaviour is paced by both day and seasonal influences.
Shorter-term cycles are more subtle and, as yet, very imperfectly known. But it does appear
that many of the shorter-term life cycles are paced by oscillating chemical or physiological
states, where a reaction can take place at one point in the cycle, but not at another.
Consider, for example, the growing twig of a pecan tree. As the twig extends, most of the
new cells being formed are of 'standard' twig tissue. But every so often, the new cells are
formed into a leaf bud, or the start of a male or female flower. How does the plant do this?
At The Fair
Presumably there is a chemical cycle going on in the twig, with the amount of some
chemical 'trigger' being built up until it reaches a threshold, initiates a changed action, and is
exhausted. The 'standard' action then continues.
In a way, it is like one of the giant swing-boat amusements at a fair. After the passengers
get in, a push is applied to the boat, and it starts to swing a little. At the end of each swing,
another push is given, and the amplitude of the swing increases.
Gradually the swing is built up, is pumped or resonated, until the boat is at its highest. At
the peak, you can do things not possible lower in the cycle -- see over the fairground fence,
perhaps. It might take 100 seconds to reach this 'trigger' or 'threshold' condition.
In the analogous chemical reaction, the cycle time to reach the activation threshold may
be very short -- in an explosive reaction it is only a tiny fraction of a second. But all such actions
and reactions do have cycle times.
Other actions are electro-chemical. For a nerve impulse to move, a receptor cell, fully
charged and ready to go, is triggered by some external event (say a bang, in the case of a hearing
impulse). This cell discharges, sending an impulse into the next cell in the nerve line, which
itself discharges into the next, and so on.
After discharge, a nerve cell must re-charge before it can operate again. This is not an
instantaneous process. Nor is the cell discharge pulse cycle instantaneous, which is why the
'speed of thought' is not actually very fast -- only about 10 metres per second.
With human vision, the receptor cells in the retina of the eye take around a twenty-fifth of
a second to recharge. This is why separate picture sequences viewed more rapidly than this,
as with the frames of a cinematograph film, appear to have continuous movement. And
television images, which are paced by the cycle of the alternating-current power supply, would
appear jerky if this supply was, say, 10 cycles/second instead of the normal 50 (60 in the US!).
In modern small computers, the suppliers proudly claim that their machine runs at, say,
'200 megahertz'. A megahertz is a million cycles per second, and in the case of these
computers, the pacemaker is a special crystal which oscillates at the rated speed. Each crystal
cycle drives one tiny operation of the machine -- without this pacing it could not operate.
Say When . . .
All the above background is leading up to a fairly obvious conclusion. That is, that regular
processes in living creatures and some of their analogues require continual regular prompting
to operate successfully. We can state this as a Proposition for all systons.
Proposition 118A***. All systons need some forms of pacemaking for successful
operation of their regular internal processes
Let us examine a real question as an illustration of this. Why do we, in democratic societies,
have General Elections? Now hold on, I am not asking why we have elections, but why they
should be all lumped together at the same time.
There could be a good linear-logic case for staggering election terms. If seats were held
for four years, each seat could be held to the end of a given month, and in each month elections
would be held for about one-forty-eighth of the seats. This would enable a small, experienced
team of election officials to be moved on from one election to the next, instead of needing to
engage a huge team of inexperienced workers for a once-in-four-years effort.
Electoral rolls could be updated and checked leisurely in sequence, instead of a great rush.
And from the public's point of view, every month would bring an opportunity for them to
express a view on current issues, as now happens with by-elections. From parliament's point
of view, the Government should have more continuity and stability, with changes to its
composition being gradual rather than holus-bolus. This stability and continuity is supposed
to be the reason why, in the Australian Senate, seats are held for two terms rather than one. In
the US, Senate seats are held for three 2-year terms.
So why don't we run things this way? Look at the situation now from the MT viewpoint,
look at what all the general-election hullaballoo is really about.
First, the general election is a pacemaker. Its occurrence switches people's interest from
other matters into that of the election, and moves them into a different section of the political
cycle, one where actions which are 'chemically impossible' most of the time do become
possible. It diverts some synenergy flow from normal to special purposes -- as if the pecan-tree
syston is preparing to make a flower bud.
Second, it thickens up the skins of the competing systons involved in the election process,
to make their boundaries more obvious and, temporarily, effective at holding the individual
systons together. Now is the time for the individual to declare which syston he is standing in,
and not sit on the fence through uncertainty or disinterest.
Finally, the actual election ritual focusses and forms new and temporary, often unnamed
and unrealized, systons, as 'the mood of the people' wavers. Ideas, discussions, 'memes',
ricochet around in the syston mix, just as when an 'ugly mood' overtakes a crowd, and
unsuspected ephemeral systons are formed, to be collapsed, discharged like a nerve cell, at the
actual election.
I suspect that this last phenomenon is a reason why pre-election opinion polls often do not
reflect actual election results. However accurate the sampling and polling of individuals
before the election may be, on the day, the ephemeral election-systons hold sway. And if
infocap and synenergy are not necessarily additive over systons (Proposition 114B), then of
course adding individual pollings together will not accurately reflect the wider syston position.
When Things Go Wrong
But back to the cockroaches. Cockroaches, like all insects, really have two brains. The
main one is above the mouth, but the second one, called the 'sub-oesophageal ganglion' is
below the gullet. It is about the size of a pinhead, and it is this ganglion which controls typical
insect movements.
It is this feature which makes it hard to stop a cockroach in its tracks. A cockroach with
its head cut off can still run about for days, and perform many functions -- even copulate.
Eating is a problem, though, and eventually the creature just runs down.
In her researches, Janet Harker developed very precise microsurgery skills, and used these
to experimentally determine where cockroaches kept their internal timing function. She was
able to track down this 'clock' to a group of just four neurosecretory cells in the suboesophageal
ganglion. She was able to prove that these cells were the real clocks by surgically
replacing the four cells in normally-conditioned cockroaches -- what we could regard as running on Greenwich Mean Time -- with those from cockroaches conditioned to a displaced
day/night cycle -- running on New Zealand time, as it were.
All the 'British' cockroaches immediately behaved as if they were running on New
Zealand time, and kept up the displaced cycle for days.
And then, in a further experiment, Harker tried the effect of transplanting single
neurosecretory cells from a time-displaced cockroach into a normally-timed one. The effect
was to to equip the cockroach with two clocks, running at different times. This experiment
gave a totally unexpected result.
All the cockroaches treated in this way quickly developed intestinal cancer and died.
Tumours in insects are very rare, but the stresses involved in having two out-of-phase
pacemakers operating at the same time were evidently enough to completely upset the normal
biochemical reactions in the creatures.
There is a possibly useful clue to cancer-causing mechanisms here. Extrapolate far
enough, and we could say that Daylight Saving causes cancer! But in this suite of articles, we are
concerned with a generalized deduction:
Proposition 118B***. Pacemakers are vital in some syston processes, but such processes
will not continue successfully with two competing pacemakers
This Proposition appears in contrast with Proposition 107C, which suggested that systons
functioned most successfully with two dominant systels in competition. There is no actual
conflict, however, as long as the distinction between a process and a systel is kept in mind.
Half-lives
It will be useful in refining the MT apparatus assembled so far if we establish some
quantitative measures for the timescales over which various things take place.
First, the measure we can use when talking about systons. This was mentioned in
MT105, when we went into the 'half-life' of civilizations, and suggested that this figure
was around 250 years.
The 'half-life' of some group of entities or objects is the time taken for half of them to reach
the end of their lives. The concept originated with radioactive elements, they have this name
because the individual atoms tend to break down and radiate energy as they do so. If we
extracted a sample of a billion Iodine-129 atoms, and placed them in a container away from
all outside influences, they would gradually break down spontaneously. After a quite definite
time, only half of them would be left. This is the half-life, for Iodine-129 it is 16 million years.
Other Iodine isotopes have different half-lives. That for Iodine-128 is only 25 minutes. And
the common form of iodine, Iodine-127, is stable -- a cautious physicist would say its half-life
is long compared to the age of the Universe.
Although we know these atomic half-lives quite precisely, we have no way at present to
predict which of the atoms will be affected, which half-billion of the sample will have broken
down after the given time. So the half-life is a convenient way of specifying lifetimes for a
group of entities with individual lifetimes which vary considerably among themselves.
This half-life is not quite the same thing as average life expectancy. Suppose you wanted
to work out the half-life for a group of people, say the current population of Australia, and
suppose you had all the relevant statistics.
If this is 1992, and you move backwards and look at the people who were born in particular
years, the proportion of these who are still alive today will decrease as you go further back.
Perhaps 95% of those born in 1982 are still alive, and only 10% of those born in 1913. The
number of years between the year in which exactly 50% of those born then are still alive, and the year
of measurement, is the half-life. According to the last available Australian Government figures
[Reference 3], the half-life of Australians as at 1986 June 30 was about 79.1 years,
whereas their life expectancy at that time was about 76.0 years. This is the average for males
and females -- females are 5-6 years ahead of males in both measurements.
Cycle Times
Cycle times are similar to lifetimes, but they apply to processes rather than entities. A
process with which we are all familiar is that the Earth turns on its axis. The time between when
the sun is due north or south from a given spot, and the next occasion when this is true, we call
a day.
Cycle times may be regular or may vary over a distribution, perhaps like that shown in
Figure 109.2. Our day-cycle is very, but not completely, regular -- at 8 am, 1992 July 1, one
'leap second' was added to Perth clocks to account for a very slight slowing down of the
Earth's rotational speed, so that day was 24 hours and one second long.
It is sometimes important to know exactly what a particular cycle time actually measures.
For example, a 'day-cycle' is not the time the Earth takes to turn once on its axis, that cycle
is about 23 hours and 56 minutes long. The four-minute difference occurs because the Earth
is itself orbiting around the Sun, and after one complete rotation it has to rotate a little more
to be in the same orientation with respect to the sun.
In this suite of articles we will sometimes use the term 'half-cycle time'. It does refer simply to half
the cycle time, and is used to be directly comparable with syston half-lives.
These timing concepts have been introduced here to allow us to 'tighten-up' some of the
Propositions used. For example, back in Proposition 113A, it was suggested that a syston
would be 'ultimately disadvantaged' by systel discrimination, and to put a limit on how
'ultimate', it was suggested that this was not longer than the syston half-life or process half-cycle
time involved.
Biorhythms
The importance of so-called biorhythms has been increasingly realized in recent years.
Many of the processes which occur in life are, in fact, critically dependent on these rhythms.
Most of these rhythms are process cycles, only a few are syston halflives. The rhythm interval
is exactly the same thing as the cycle time, the time taken to get back to the same point in the
cycle.
It will be apparent that not only living creatures, but in fact any sort of syston, may have
the equivalent of biorhythms.
Rituals, Rites, Rhythms, and Cycle Pumping
A feature of a cycle is that it moves through varying conditions until it gets back to the same
point in the cycle. Within any complete cycle there may be any number of smaller cycles
operating. Within an average sleep cycle, for example, your heart may pump around 33,600
times.
There seems to be little doubt that when you come to look at what is actually going on
within a process cycle, the progression of the cycle is often dependent on so-called 'pumping'
effects. When you pump up the tyre on a bicycle, a particular sort of cycle, progressive
inflation of the tyre depends on you compressing the batch of air in the pump cylinder to the
point where its pressure becomes greater than that in the tyre itself. Only at that point will the
tyre valve open to allow the additional air in.
A great many of the cycles we will come across in the MT analyses which follow will be
pumped cycles. Like the pumped laser mentioned in MT117, or the fairground swingboat
mentioned in this article, the process cycle is completed by progressive injection of a series of
sub-pulses of energy.
We will frequently find that the pumping mechanisms involved in MT processes and
syston lives are what are usually called rituals, rites, and rhythms. In more official terms, they
may be called standard operating procedures or something similar.
Proposition 118C***. Syston processes are usually pumped through rituals and similar
synenergy-injection procedures
A familiar example of rituals is those involved in religious services, say a marriage
ceremony. The congregation assemble, the vicar or priest appears, there may be music or
songs, readings and addresses, the wedding text is read and responded to, rings are exchanged.
Once started, the whole process continues on inexorably, each little sub-ritual pumping it on
a little further.
Similar rituals are involved in forming and developing all sorts of systons. In a temporary
orchestral-performance-audience syston, the 'atmosphere' is built up with the entry and
seating of the audience, the appearance of the members of the orchestra, the tuning-up, the
standard pre-coughing, peaking with the appearance of the conductor. In longer-lasting
systons, such as production of a legislative body, the rituals involved in the election procedures
may be far more extended.
We will not labour the details of rituals here -- the reader will be able to pick out the rituals
involved in familiar systons of every sort. We should, however, make one point. Rituals may
be effective, may be essential, without us having any clear idea of how they work.
* * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
References
(Full list of references at MTRefs)
[3]. Australian Life Tables, 1985-87. Australian Government Actuary.
[23]. Ritchie R Ward. The Living Clocks. Knopf, NY, 1971.
Go to the "Matrix Thinking: How Society Works" Home Page
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Version 3.0, 2014 Jul 10, Reworked from chapter 118 of "Matrix Thinking" as one article in a suite on the World Wide Web.
