João Francisco Botelho

Embryos resolve the enigmatic origin of the theropod wishbone

The origin of the avian wishbone (furcula)—present since theropod dinosaurs—remains unsolved. Its homology is still debated, with competing hypotheses proposing derivation from the clavicles, the interclavicle, or both. To obtain comparative developmental evidence, we studied oss...

Transient cartilages and interdigital vasculature organization in the embryonic duck foot

Abstract The evolution of webbed limbs represents a recurrent adaptation to aquatic life in tetrapods, facilitated by the dynamics of embryonic digit development. Digits form at the distal tip of the limb bud as cartilage condensations surrounded by mesenchymal cells, a process d...