Supplementary Fig 4

Ontogenetic trajectories of the conch width index, umbilical width index and whorl expansion rate, as well as the two new parameters, apertural surface area index and buccal mass area index, of three ammonoid species: A – *Hammatocyclus pollex* Ebbighausen, Korn & Bockwinkel, 2010, specimen MB.C.18601.7 (Early Carboniferous, Gourara, Algeria), B – *R**evilloceras granofalcatum *(Kullmann, 1961), specimen MB.C.9090.1 (Early Carboniferous, Anti-Atlas, Morocco) and C – *Metalegoceras sundaicum* (Haniel, 1915), specimen MNHN Paris 1925-16 B7532 (Early Permian, Timor)*.