Early Development of the Shoulder Girdle and Sternum in Marsupials (Mammalia: Metatheria)

The following elements can be observed in the marsupial breast-shoulder apparatus during embryogenesis: scapula, metacoracoid, procoracoid, first rib, paired sternal elements, unpaired sternal element, and clavicle. The unpaired sternal element fuses with the paired sternal element, generating the uniform manubrium sterni.