A new tool for determining degrees of mineralization in fossil amphibian skeletons : The example of the Late Palaeozoic branchiosaurid Apateon from the Autun Basin, France

• Studying ontogenetic features of fossil tetrapods is of major interest for investigating the adaptive strategies of early tetrapods to their palaeoenvironments. To determine the degree of calcification of skeletal elements, biologists have until now relied on X-ray radiographs of organisms or isolated bones, or on thin sections. An X-ray tomographic scan of Apateon, a Carboniferous - Permian branchiosaurid from the Autun Basin, France, reveals distinct density properties related to different mineralized tissues (calcified cartilage versus bone). The rendering of Apateon as a "test individual" provides a 3D map of the degrees of ossification of the axial and cranial elements. The combination of these anatomical observations with histological information from classical thin sections made in limb bones of several other specimens of the same locality allows the detailed determination of their ontogenetic stage. A comparison with the well-known specimens of the Saar-Nahe Basin, Germany, makes it possible to investigate the influence of different palaeoenvironments on ontogenetic features.

Subject headings

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Geologi (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Geology (hsv//eng)

Keyword

Branchiosaurids

Late Palaeozoic

Ontogeny

Ossification sequence

Palaeoecology

Skeletochronology

Historical geology and palaeontology

Historisk geologi och paleontologi

Biologi med inriktning mot evolutionär organismbiologi

Biology with specialization in Evolutionary Organismal Biology

Publication and Content Type

ref (subject category)

art (subject category)