Synchrotron Reveals Early Triassic Odd Couple: Injured Amphibian and Aestivating Therapsid Share Burrow
Open Access
- 21 June 2013
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 8 (6), e64978
- https://doi.org/10.1371/journal.pone.0064978
Abstract
Fossorialism is a beneficial adaptation for brooding, predator avoidance and protection from extreme climate. The abundance of fossilised burrow casts from the Early Triassic of southern Africa is viewed as a behavioural response by many tetrapods to the harsh conditions following the Permo-Triassic mass-extinction event. However, scarcity of vertebrate remains associated with these burrows leaves many ecological questions unanswered. Synchrotron scanning of a lithified burrow cast from the Early Triassic of the Karoo unveiled a unique mixed-species association: an injured temnospondyl amphibian (Broomistega) that sheltered in a burrow occupied by an aestivating therapsid (Thrinaxodon). The discovery of this rare rhinesuchid represents the first occurrence in the fossil record of a temnospondyl in a burrow. The amphibian skeleton shows signs of a crushing trauma with partially healed fractures on several consecutive ribs. The presence of a relatively large intruder in what is interpreted to be a Thrinaxodon burrow implies that the therapsid tolerated the amphibian’s presence. Among possible explanations for such unlikely cohabitation, Thrinaxodon aestivation is most plausible, an interpretation supported by the numerous Thrinaxodon specimens fossilised in curled-up postures. Recent advances in synchrotron imaging have enabled visualization of the contents of burrow casts, thus providing a novel tool to elucidate not only anatomy but also ecology and biology of ancient tetrapods.Keywords
This publication has 33 references indexed in Scilit:
- A BURROW CAST WITH LYSTROSAURUS SKELETAL REMAINS FROM THE LOWER TRIASSIC OF SOUTH AFRICAPALAIOS, 2010
- KATBERGIA GEN. NOV., A NEW TRACE FOSSIL FROM UPPER PERMIAN AND LOWER TRIASSIC ROCKS OF THE KAROO BASIN: IMPLICATIONS FOR PALAEOENVIRONMENTAL CONDITIONS AT THE P/TR EXTINCTION EVENTPalaeontology, 2008
- FAUNAL AGGREGATION IN THE EARLY TRIASSIC KAROO BASIN: EARLIEST EVIDENCE OF SHELTER-SHARING BEHAVIOR AMONG TETRAPODS?PALAIOS, 2006
- The recovery of terrestrial vertebrate diversity in the South African Karoo Basin after the end-Permian extinctionComptes Rendus Palevol, 2005
- Earliest evidence of cynodont burrowingProceedings. Biological sciences, 2003
- Changing Fluvial Environments and Vertebrate Taphonomy in Response to Climatic Drying in a Mid-Triassic Rift Valley Fill: The Omingonde Formation (Karoo Supergroup) of Central NamibiaPALAIOS, 2002
- Vertebrate Burrow Complexes from the Early Triassic Cynognathus Zone (Driekoppen Formation, Beaufort Group) of the Karoo Basin, South AfricaPALAIOS, 2001
- Vertebrate Taphonomy of Late Permian Floodplain Deposits in the Southwestern Karoo Basin of South AfricaPALAIOS, 1993
- Helical burrow casts of therapsid origin from the Beaufort Group (Permian) of South AfricaPalaeogeography, Palaeoclimatology, Palaeoecology, 1987
- Vertebrate BurrowsPublished by Springer Science and Business Media LLC ,1975