Life & Physiology
the whole axis, end to end · read card by card
Life & Physiology
The body organizing the rhythms, shapes and set-points that keep it going.
The body is full of things that hold a rhythm, a shape or a set-point, and come back
when you push them. Every one of them needs throughput to do it, so needing energy from outside
cannot sort them, the same trap as everywhere in this laboratory. What sorts them is the
canonical question: does a structure’s own activity close the loop that keeps it going, or
is the loop supplied from outside and the structure only carrying it?
Physiology is one domain where the
taxonomy shows up from end to end. A circadian clock that
free-runs in the dark sits in the recursive middle. A muscle held in a sustained contraction by an outside
stimulus is an attractlet. A whole cell that builds and repairs its own edge is the one clean case of sovereignty on the
page. Read each card for where its order comes from, not whether it recovers: everything here
recovers.
How to read a card
Each card is one physiological structure. Its small tag is an authored reading of the real
structure against the taxonomy map, a teaching device, not
a measurement. The kernel says nothing about physiology.
Blue, recursive · not sovereign: the structure’s own activity closes
its loop, and it falls short of sovereignty as the flame on the
Sovereignty page does. Whether it is a base or a
coordination attractor is noted on the card. Deep blue, sovereign candidate: all four
conditions read as satisfied; this is the right-hand end of the axis. Red, natural attractlet
· § 7.4: “a naturally-occurring non-recursive structure that exhibits
attractor-like behavior under external driving.” Gold, reading open: the test
does not settle it, and the card says why.
And the direction of the debt matters. Physiology described the circadian clock, the
action potential and homeostasis long before this framework existed. The framework did not discover them
and takes no credit for them. What it asks is narrower and comes second: what kind of persistence is
each of these actually instantiating?
Subcellular · molecular oscillators
can a molecular loop keep its own rhythm with nothing outside setting the pace?
The Circadian Clock
recursive · not sovereign (base)
A loop of genes and proteins that build up, switch themselves off, break down, and start again,
cycling roughly every twenty-four hours. Light does not drive it; light only resets its phase.
BasinThe starting concentrations that settle into the same near-24h cycle instead of flatlining. Nudge a protein level and the rhythm re-phases back to its own period. Why recursive: it free-runs in constant darkness, keeping that period for weeks with no day outside, so the order is self-produced. A base attractor, a loop that closes on its own prior state and nothing more.
Read the page →
Glycolytic Oscillation
recursive · not sovereign (base)
Extract the glycolysis machinery from yeast, feed it sugar in a stirred flask, and the
concentrations oscillate on their own, a chemical clock with no cell around it.
BasinThe starting mixtures and feed rates from which the concentrations settle into a sustained oscillation rather than a dead steady state. Disturb it and it returns to the same cycle. Why recursive: it oscillates in a test tube from the feedback in its own enzyme kinetics, a sibling of the Belousov reaction, order a set of reactions makes for itself.
Read the page →
Cellular
can a cell make and hold its own edge, and pay for it from inside?
The Living Cell
sovereign candidate · the anchor case
A single cell runs closed metabolic loops, coordinates thousands of processes, and then does the
two things nothing else on this page does: it builds and repairs its own membrane, and it pays its
own maintenance from within. The right-hand end of the axis.
BasinThe perturbed internal states, damaged membrane, disturbed metabolite pools, that the cell’s own activity repairs back to a living regime. Push it far enough past the edge and it lyses instead of returning. Why sovereign: its molecules turn over constantly yet the same cell persists, because identity lives in the self-maintained regime and it produces and defends its own boundary, the line the recursive middle never crosses. The taxonomy page’s own worked example.
Read the sovereign case →
The Action Potential
reading open
A nerve or muscle cell crosses a voltage threshold, fires a single spike, and resets. One clean
pulse, and then it is over until the next stimulus.
BasinThere is a resting state the membrane returns to after every spike, and small sub-threshold nudges decay back to it, which looks like a basin. But the spike itself is a one-way excursion, not a return. Why open: a single fire-and-reset is a threshold event, not obviously a sustained recursion. A train of self-triggered spikes (a pacemaker cell) is recursive; one isolated spike, waiting on an outside stimulus, may be closer to a supplied event. The test does not settle it.
Reading · no live panel yet
The Epigenetic Landscape
recursive · not sovereign (base) · runnable now
Two genes that each switch themselves on and switch each other off give a cell three valleys: one
for each fate, and one in the middle where it has not yet chosen. A number shared by both genes can close
the middle valley without favouring either fate. A methyl mark on one gene breaks that balance and
decides which valley the cells can reach. Runnable now.
BasinThe gene levels that settle into the same valley. Push a committed cell and, with no marks, it is lifted back into the middle. Let the marks follow the genes and the silent gene gets methylated, the valley the push would land in disappears for that cell, and every cell comes back. Why recursive: each valley is held by the genes switching themselves on, with nothing outside re-preparing the state; when the model's marks follow the genes, the cell also writes the numbers that reshape its own landscape. The genes are made by the cell, so any sovereignty verdict belongs to the whole cell.
Enter simulation →
Neural · circuit
can a circuit hold a state with nothing outside holding it?
The Fly's Compass
recursive · not sovereign (base) · runnable now
In the fruit fly's brain, a ring of neurons carries a single bump of activity, and where the bump
sits on the ring tracks which way the fly is facing. When the fly turns, the bump moves around the ring
with it. In the dark, the bump stays where it was. Runnable now.
BasinThe starting patterns of activity that grow into one bump. Activity too weak, too narrow or spread too evenly around the ring dies out instead, and in the dark the ring then stays silent. Once formed, the bump can sit anywhere: every heading is an equally good resting place, so in darkness it slowly drifts. Why recursive: neighbouring neurons excite one another, which keeps the bump alive, and inhibition across the ring allows only one bump. When Kim et al. (2017) forced a bump at a second spot with light, the old one faded out and the new one stayed after the light went off. Cut the wiring and the bump is gone at once. Turning moves the bump around the ring; the landmark anchors it and, in this model, can start one on a silent ring, but neither keeps it alive. The neurons and their wiring are made by the fly, so any sovereignty verdict belongs to the whole animal.
Enter simulation →
Organism · regulatory
is the set-point the body’s own doing, or handed to it?
Homeostasis
recursive · a loop inside a larger one · runnable now
Body temperature held near 37°C, blood glucose held in a narrow band: feedback that pushes a
wandering value back toward where it is held, against constant disturbance. Runnable now.
BasinThe displaced values, a chill, a load of heat from hard work, that the regulatory loops drive back and hold against constant disturbance. Overwhelm them (cold water, heat the loops cannot shed) and the value leaves the basin and runs away. The set-point question, answered: there is no stored 37°C. Several loops with their own thresholds pull against each other, and 37 is where they balance. A fever is the body moving those thresholds itself. What stays open is where the line is drawn: the loop alone does not make its own parts, and the organism it belongs to does.
Enter simulation →
Muscle Tetanus
natural attractlet · § 7.4
Stimulate a muscle fast enough and its twitches fuse into one smooth, sustained contraction that
holds as long as the stimulus does.
BasinThe contraction holds steady at a given stimulus frequency and returns to that level after a twitch is disturbed, a basin whose location is set entirely by the drive: change the frequency and the whole plateau moves with it. Why attractlet: it contracts at exactly the frequency it is stimulated and stops the moment the drive stops. Pure carried order, none of it released or timed by the muscle itself, the plain § 7.4 case beside the circadian clock that keeps its own time.
Reading · no live panel yet
Together the cards on this page cross the
taxonomy: a clock that keeps its own time (base), a cell that
holds its own edge (sovereign), and a muscle that holds its contraction only while it is driven
(attractlet). One body, end to end.
The rest of the axis:
Living Structures →, the recursive
genus; and Attractlets →, non-recursive
order handed in from outside.
← Back to the Laboratory