Phyllotaxis
the spirals are counted, not admired
Concept

Allometry — where it appears

How a measurement of an organism changes with its size, as a power of that size rather than in proportion to it.

Named by 2 essays across one field — each of them below, with the objects they name alongside it.

Also named here as transport — the same set of essays touches all of them, so they are one junction rather than several.

1101001000100000.2000.4000.6000.8001daughter ratio — the smaller branch over the largerjunctions needed to tell Murray's rule from Da Vinci'san even fork — one is enougha twig — 2195the same tree, built at an exponent of 3, measured twicethe truth — 350 even forks3.0150 twigs1.692% error per radius · 47% of twigs impossiblemargin 0.11% against 2.8% noise

Which junctions say anything

Da Vinci's rule and Murray's law differ by 12% at an even fork and by a tenth of a per cent at a twig. So one even fork settles which is right, and two thousand twigs do not — a factor of two thousand across a tree, decided entirely by the shape of the junction and not by how carefully it is measured.

branching · exponent 1101001000100000.2000.4000.6000.8001daughter ratio — the smaller branch over the largerjunctions needed to tell Murray's rule from Da Vinci'san even fork — one is enougha twig — 2195the same tree, built at an exponent of 3, measured twicethe truth — 350 even forks3.0150 twigs1.692% error per radius · 47% of twigs impossiblemargin 0.11% against 2.8% noise

A sample that is confidently wrong

Fifty lopsided junctions from a tree built at an exponent of exactly 3 return 1.7, with an interval that excludes 3 and excludes 2 as well. The sample carrying almost no information does not give a wide answer — it gives a narrow wrong one, and the cause is a selection nobody applies on purpose.

branching · exponent

Named alongside it

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

Branching exponentDa Vinci's ruleFittingMeasurementMurray's lawSamplingSpecimenSummary statisticSurveyTransportBiasExponent fitting

All concepts