Phyllotaxis
the spirals are counted, not admired
Concept

Selection effect — where it appears

2 essays name this object, across one field. What follows is each of them, and the objects they name alongside it.
golden 137.51°55 and 89FibonacciLucas 99.50°47 and 76Lucas151.14°50 and 81neither77.96°37 and 60neithercounted from the pointsone sequence per branch

Fibonacci is a branch, not a law

Fibonacci counts come from one branch of the model. The Lucas branch — which the same rule reaches at a different growth rate — gives 47 and 76, and neither is a Fibonacci number. The sequence is a consequence of an angle rather than a property of plants.

wrong · fibbranch -0.20000.2000.4000.6000.5000.75011.251.50divergence scatter, in degrees — the one quantity a plant offerscorrelation between one divergence and the next4 runs per point · band ±0.13every point is a lattice

What a quiet plant is worth

Almost every measurement gets easier as the effect gets larger. This one gets harder — a stem's divergence sequence stops carrying information about its noise at precisely the scatter where the noise becomes obvious. The specimens worth measuring are the ones that look least interesting.

wrong · survey spec

Named alongside it

The objects these essays reach for when they reach for this one.

Divergence angleSurveyAttractorAutocorrelationBranchContinued fractionConvergentsDiscriminationEvidenceFibonacciφ, the golden ratioHonest limits

All concepts