Morphogenic Movements: Somitogenesis
Mesoderm-derived: Somites; Muscle
Stage of Development: Embryo
This Children’s python embryo (Antaresia children) is at early Stage 35 and was collected shortly after being laid. It has roughly 200 somites and may develop another hundred or so before the termination of somitogenesis. Somites are condensed blocks of mesoderm that give rise to bone and cartilage of the vertebrae and ribs, muscles, and dermis. The somites can be seen on either side of the spine along the length of the snake embryo. Adult snakes can develop anywhere from 200-500 vertebrae, depending on the species.
Dr. Dale Denardo provided the Children's python eggs.
Kusumi, K., May, C.M., Eckalbar, W.L. A large-scale view of the evolution of amniote development: insights from somitogenesis in reptiles. Curr. Opin. Genet. Dev. 2013, 23:1-17.
Hubert, J., Dufaure, J.P. Table de développement de la vipère aspic: Vipera aspis. L. Bulletin de la Société Zoologique de France, 1968, 93:135–148.
Lourdais, Olivier. Heulin, Benoit. Denardo, Dale. Thermoregulation during gravidity in the children’s python (Antaresia childreni): a test of the preadaptation hypothesis for maternal thermophily in snakes. Biological Journal of the Linnean Society. 2008, 93:499-508.