EVOMORPH — Theme ONTOGENY

How does ontogeny shed light on morphological evolution?

• Led by Helder Gomes Rodrigues and Alan Pradel

The analysis of ontogenetic series—spanning prenatal to senescent stages in both extinct and extant species—is vital for decoding the evolution of morphological patterns. By characterizing developmental sequences and structural constraints, we can effectively address how anatomical structures emerge and evolve. Our research focuses on growth dynamics of selected structures (e.g., rhythm, heterochrony, replacement - metamorphosis - regeneration) and the evaluation of their homology. This includes embryonic morphological data, which is complementary to the morphogenetic and genetic data obtained from the development of extant taxa. These data allow us to understand the establishment of novel morphologies in fossil forms and to enrich existing evo-devo studies. The team offers specialized expertise across several ontogenetic models, including dental development, vertebrate head development and craniofacial ossification, ammonoid shell growth, and crustacean metamorphosis.

3D reconstructions in left lateral view of the head of modern embryonic ( A and B) cartilaginous fishes (sharks, rays and chimaeras) used to infer the morphology of an adult Carboniferous fossil from USA (C). Grey: braincase, jaws and pectoral girdle. Colors: branchial skeleton and associated arterial and venous systems. Image layout by A. Lethiers.