The petrosal and basicranial morphology of Protoceras celer.

Area of Science:

• Paleontology
• Mammalian Evolution
• Comparative Anatomy

Background:

• The phylogenetic placement of Protoceratidae within Artiodactyla has been debated for over a century.
• Conflicting evidence from petrosal morphology has suggested relationships with both camelids and ruminants.
• This has led to questions about the reliability of basicranial characters in artiodactyl phylogenetics.

Purpose of the Study:

• To re-examine the petrosal morphology of Protoceras celer using advanced imaging techniques.
• To clarify the phylogenetic position of protoceratids within the Artiodactyla.
• To assess the conservation of petrosal morphology within the Protoceratidae family.

Main Methods:

• Computed tomography (CT) scanning of a Protoceras celer fossil.
• In situ imaging of the petrosal bone within the skull.
• Comparative analysis of petrosal morphology with other protoceratids, camelids, and ruminants.

Main Results:

• The petrosal morphology of Protoceras celer is consistent with that of other protoceratids.
• Contrary to previous interpretations, petrosal morphology appears conserved across the Protoceratidae lineage.
• This finding supports a unified understanding of protoceratid basicranial anatomy.

Conclusions:

• Petrosal morphology is a reliable indicator of phylogenetic relationships within Protoceratidae.
• The study resolves conflicting evidence regarding the placement of protoceratids, suggesting a closer relationship to ruminants.
• This research validates the utility of basicranial characters in understanding artiodactyl evolution.