Cranial osteogenesis in Monodelphis domestica (Didelphidae) and Macropus eugenii (Macropodidae).

Journal Article (Journal Article)

The pattern of onset and general rate of cranial ossification are compared in two marsupials, Monodelphis domestica (Didelphidae) and Macropus eugenii (Macropodidae). In both species a similar suite of bones is present at birth, specifically those surrounding the oral cavity and the exoccipital, and in both postnatal events follow a similar course. The facial skeleton matures more rapidly than the neurocranium, which is characterized by an extended period of ossification. Most dermal bones begin ossification before most endochondral bones. Endochondral bones of the neurocranium are particularly extended in both the period of onset of ossification and the rate of ossification. These data confirm suggestions that morphology at birth is conservative in marsupials and we hypothesize that the pattern of cranial osteogenesis is related to two distinct demands. Bones that are accelerated in marsupials are correlated with a number of functional adaptations including head movements during migration, attachment to the teat, and suckling. However, the very slow osteogenesis of the neurocranium is probably correlated with the very extended period of neurogenesis. Marsupials appear to be derived relative to both monotreme and placental mammals in the precocious ossification of the bones surrounding the oral cavity, but share with monotremes an extended period of neurocranial osteogenesis.

Full Text

Duke Authors

Cited Authors

  • Clark, CT; Smith, KK

Published Date

  • February 1993

Published In

Volume / Issue

  • 215 / 2

Start / End Page

  • 119 - 149

PubMed ID

  • 8445660

Electronic International Standard Serial Number (EISSN)

  • 1097-4687

International Standard Serial Number (ISSN)

  • 0362-2525

Digital Object Identifier (DOI)

  • 10.1002/jmor.1052150203


  • eng