Concept
Description versus mechanism — where it appears
2 essays name this object, across 2 fields. What follows is each of them, and the objects they name alongside it.
L-systems describe, they do not explain
Two rewriting rules and a turtle produce something indistinguishable from a plant, and there is no plant in it — no light, no water, no auxin, no mechanics. That is worth demonstrating precisely because the output is so convincing.
A growing organ is part of the rule
Every model on this site places primordia on a surface and then treats the surface as furniture. But the surface grows between one placement and the next, and that growth reaches the rule through the only channel it has — where the neighbours are. What looks like a boundary condition turns out to be a term in the model.
Named alongside it
The objects these essays reach for when they reach for this one.
AuxinBasinBranchElongationEpitheliumHonest limitsL-systemsMechanismMeristem growthModel scopeNoiseThe placement rule