Investigation of a bone lesion in a gorgonopsian (Synapsida) from the Permian of Zambia and periosteal reactions in fossil non-mammalian tetrapods.

Autor: Kato KM; Department of Biological Sciences, University of Southern California, Los Angeles, CA 90089-0371, USA., Rega EA; College of Osteopathic Medicine of the Pacific and the Graduate College of Biomedical Sciences, Western University of Health Sciences, Pomona, CA 91766-1854, USA., Sidor CA; Department of Biology and Burke Museum, University of Washington, Seattle, WA 98105, USA., Huttenlocker AK; Department of Integrative Anatomical Sciences, University of Southern California, Los Angeles, CA 90033, USA.
Jazyk: angličtina
Zdroj: Philosophical transactions of the Royal Society of London. Series B, Biological sciences [Philos Trans R Soc Lond B Biol Sci] 2020 Mar 02; Vol. 375 (1793), pp. 20190144. Date of Electronic Publication: 2020 Jan 13.
DOI: 10.1098/rstb.2019.0144
Abstrakt: While only distantly related to mammals, the anatomy of Permian gorgonopsians has shed light on the functional biology of non-mammalian synapsids and on the origins of iconic 'mammal-like' anatomical traits. However, little is known of gorgonopsian behaviour or physiology, which would aid in reconstructing the paleobiological context in which familiar mammalian features arose. Using multi-modal imaging, we report a discrete osseous lesion in the forelimb of a late Permian-aged gorgonopsian synapsid, recording reactive periosteal bone deposition and providing insights into the origins and diversity of skeletal healing responses in premammalian synapsids. We suggest that the localized lesion on the anterolateral (preaxial) shaft of the left radius represents acute periostitis and, conservatively, most likely developed as a subperiosteal haematoma with subsequent bone deposition and limited internal remodelling. The site records an inner zone of reactive cortical bone forming irregular to radial bony spicules and an outer, denser zone of slowed subperiosteal bone apposition, all of which likely occurred within a single growing season. In surveys of modern reptiles-crocodylians, varanids-such haematomas are rare compared to other documented osteopathologies. The extent and rapidity of the healing response is reminiscent of mammalian and dinosaurian bone pathologies, and may indicate differing behaviour or bone physiology compared to non-dinosaurian reptiles. This report adds to a growing list of putative disease entities recognized in early synapsids and broadens comparative baselines for pathologies and the evolution of bone response to disease in mammalian forebears. This article is part of the theme issue 'Vertebrate palaeophysiology'.
Databáze: MEDLINE