Title: Developmental and evolutionary origin of the tetrapod neck
The passage from aquatic to land lifestyle constituted a major event in the evolution of vertebrates and was accompanied by several morphological adaptations including the transition from fins to limbs. Although this latter feature has been studied extensively, the emergence of the neck has received less attention.
The neck is a morphological innovation that emerged congruent with limbs during the vertebrate water-to-land transition and that required profound developmental rearrangements. In vertebrates, the muscular systems of the head and trunk have different embryonic mesodermal origins regulated by distinct gene regulatory networks. The neck, that connects the head to the trunk, has mixed embryonic mesodermal origins and its evolutionary history remains elusive.
In this talk, I will describe how we have evaluated the relative contribution of mesodermal cell populations to the emergence and adaptation of the tetrapod neck by combining comparative embryology and anatomy approaches in key vertebrate organisms and by performing genetic lineage tracing strategies in zebrafish and mouse embryos, high-resolution fluorescent imaging and micro-CT scan analyses.