FGM: Fisher’s geometrical model of adaptation. |

DFE: Distribution of the fitness effects of a set of mutations, among a given set of genotypes (*de novo* random mutants, standing variants at equilibrium, etc.), in a given environment and/or genetic background. |

LSD: Limit spectral distribution (distribution of eigenvalues) of a matrix as its dimensions get large. |

i.i.d: identically and independently distributed (a set of values all drawn independently from the same distribution). |

Developmental function relating mutable traits (**x**) and optimized traits (**y**), see Figure 1. |

Pathway coefficients relating mutable trait *j* to optimized trait *i* [the first derivatives of at the parent phenotypic position], gathered into the matrix **B**. |

M-P law (): Marchenko–Pastur law with ratio index *β* and scale parameter *ζ*. |

with Identity matrix in *k* dimensions. |

pdf of the LSD of the matrix **X** and corresponding Shannon transform, respectively (same conventions for all other transforms). |