Vascularization in Ornamented Osteoderms: Physiological Implications in Ectothermy and Amphibious Lifestyle in the Crocodylomorphs?
- 9 November 2017
- journal article
- research article
- Published by Wiley in The Anatomical Record
- Vol. 301 (1) , 175-183
Abstract
Vascularization in the core of crocodylian osteoderms, and in their superficial pits has been hypothesized to be a key feature involved in physiological thermoregulation and/or acidosis buffering during anoxia (apnea). However, up to now, there have been no quantitative data showing that the inner, or superficial, blood supply of the osteoderms is greater than that occurring in neighboring dermal tissues. We provide such data: our results clearly indicate that the vascular networks in both the osteoderms and the pits forming their superficial ornamentation are denser than in the overlying dermis. These results support previous physiological assumptions and indicate that vascularization in pseudosuchian (crocodylians and close relatives) ornamented osteoderms could be part of a broad eco‐physiological adaptation towards ectothermy and aquatic ambush predation acquired by the crocodylomorphs during their post‐Triassic evolution. Moreover, regressions demonstrate that the number of enclosed vessels is correlated with the sectional area of the cavities housing them (superficial pits and inner cavities). These regressions can be used to infer the degree of vascularization on dry and fossilized osteoderms and thus document the evolution of the putative function of the osteoderms in the Pseudosuchia. Anat Rec, 2017. © 2017 Wiley Periodicals, Inc. Anat Rec, 301:175–183, 2018.Keywords
This publication has 33 references indexed in Scilit:
- Palaeohistology and external microanatomy of rauisuchian osteoderms (Archosauria: Pseudosuchia)Palaeontology, 2011
- Sculpture and vascularization of dermal bones, and the implications for the physiology of basal tetrapodsZoological Journal of the Linnean Society, 2010
- The evolution of Metriorhynchoidea (mesoeucrocodylia, thalattosuchia): an integrated approach using geometric morphometrics, analysis of disparity, and biomechanicsZoological Journal of the Linnean Society, 2010
- Bone microstructures and mode of skeletogenesis in osteoderms of three pareiasaur taxa from the Permian of South AfricaJournal of Evolutionary Biology, 2009
- The integumentary skeleton of tetrapods: origin, evolution, and developmentJournal of Anatomy, 2009
- Development of the dermal skeleton in Alligator mississippiensis (Archosauria, Crocodylia) with comments on the homology of osteodermsJournal of Morphology, 2008
- On the bone histology of some Triassic pseudosuchian archosaurs and related taxaAnnales de Paléontologie, 2003
- Plasma ion balance of submerged anoxic turtles at 3°C: The role of calcium lactate formationRespiration Physiology, 1982
- Book ReviewEuropean Journal of Plant Pathology, 1982
- Behavioral and Physiological Thermoregulation of CrocodiliansAmerican Zoologist, 1979