Dinosaur egg volcanic taphonomy (Cretaceous, South Korea) + Colossosuchus (phytosaur, Triassic of India) community with bone infection epidemic
22 views
Skip to first unread message
Ben Creisler
Feb 19, 2026, 4:20:27 PM (11 hours ago) Feb 19
to DinosaurMa...@googlegroups.com
Ben Creisler
New papers:
Seongyeong Kim, Yuong-Nam Lee, Noe-Heon Kim & Yong Sik Gihm (2026)
Volcanic taphonomy of dinosaur eggs on Wi Island, South Korea: A reassessment of nesting chronology and cross-cutting relationships
Cretaceous Research 106347
doi: https://doi.org/10.1016/j.cretres.2026.106347
https://www.sciencedirect.com/science/article/abs/pii/S0195667126000364
Volcanically active landscapes can overprint every stage of the vertebrate-nesting record, from site selection to final fossil preservation. Dinosaur eggs from the lowermost successions of Wi Island, South Korea (latest Coniacian–earliest Santonian), exemplify this influence: Propagoolithus widoensis is confined to two volcanic-overprint facies: (i) a clutch thermally altered by contact metamorphism near a basaltic dike and (ii) fragments mechanically entrained in a mud-dike mobilized by volcanic loading, whereas the third facies, (iii) isolated, heavily weathered eggshells within volcaniclastic-rich mudstones, belongs to cf. Spheroolithidae. In contrast to earlier suggestions that dinosaurs nested on pre-existing metamorphosed rock, our field evidence shows hornfels formation postdated nesting. Cross-cutting relationships, along with the hardness of the metamorphosed substrate, indicate that excavating into such rigid material would have been infeasible, reaffirming that the nests were established before the igneous intrusion. By contrast, the injection of clastic dike suggests that rapidly deposited ash or lava layers triggered ductile deformation, displacing eggshell fragments upward. In the southwestern fossil locality, sparse and weathered eggs suggest more variable floodplain conditions or sporadic nesting. Collectively, these findings underscore the importance of volcanic processes, including intrusions, ash deposition, and dike injection, in shaping dinosaur egg taphonomy, even within a single sedimentary basin.
====
====
Seongyeong Kim, Yuong-Nam Lee, Noe-Heon Kim & Yong Sik Gihm (2026)
Volcanic taphonomy of dinosaur eggs on Wi Island, South Korea: A reassessment of nesting chronology and cross-cutting relationships
Cretaceous Research 106347
doi: https://doi.org/10.1016/j.cretres.2026.106347
https://www.sciencedirect.com/science/article/abs/pii/S0195667126000364
Volcanically active landscapes can overprint every stage of the vertebrate-nesting record, from site selection to final fossil preservation. Dinosaur eggs from the lowermost successions of Wi Island, South Korea (latest Coniacian–earliest Santonian), exemplify this influence: Propagoolithus widoensis is confined to two volcanic-overprint facies: (i) a clutch thermally altered by contact metamorphism near a basaltic dike and (ii) fragments mechanically entrained in a mud-dike mobilized by volcanic loading, whereas the third facies, (iii) isolated, heavily weathered eggshells within volcaniclastic-rich mudstones, belongs to cf. Spheroolithidae. In contrast to earlier suggestions that dinosaurs nested on pre-existing metamorphosed rock, our field evidence shows hornfels formation postdated nesting. Cross-cutting relationships, along with the hardness of the metamorphosed substrate, indicate that excavating into such rigid material would have been infeasible, reaffirming that the nests were established before the igneous intrusion. By contrast, the injection of clastic dike suggests that rapidly deposited ash or lava layers triggered ductile deformation, displacing eggshell fragments upward. In the southwestern fossil locality, sparse and weathered eggs suggest more variable floodplain conditions or sporadic nesting. Collectively, these findings underscore the importance of volcanic processes, including intrusions, ash deposition, and dike injection, in shaping dinosaur egg taphonomy, even within a single sedimentary basin.
====
Pratyusha Sarkar & Sanghamitra Ray (2026)
Extensive radial fibrolamellar bone tissue in long bones reveals an epidemic of persistent, recurrent, and non-traumatic bone infection in a juvenile-dominated phytosaur (Archosauria; Pseudosuchia) community
The Anatomical Record (advance online publication)
doi: https://doi.org/10.1002/ar.70160
https://anatomypubs.onlinelibrary.wiley.com/doi/10.1002/ar.70160
We report for the first time an epidemic of persistent and recurrent bone infection in a Late Triassic juvenile-dominated phytosaur community. Bone histology of long limb bones and dorsal ribs of nine out of 21 individuals of Colossosuchus techniensis revealed aggressive periosteal growth as represented by distinct crescentic zone(s) of radial fibrolamellar bone tissue in the form of a sunburst pattern of the vascular channels and extensive secondary resorption at the mid- and outer cortical region. We propose that this Colossosuchus community suffered an epigenetic disease influenced by some exogenous factors and/or environments. The possibility of various diseases is reviewed, and within an extant phylogenetic bracketing approach, the most probable cause is inferred to be bacterial infection, especially in the form of osteomyelitis. Alternating occurrences of normal and diseased bone tissue in several limb bones, albeit in several individuals, suggest that the bone infection was persistent and recurrent, and resulted in a suppressed immunodefence system and restricted mobility that ultimately caused the demise of the phytosaur community.
=====
Extensive radial fibrolamellar bone tissue in long bones reveals an epidemic of persistent, recurrent, and non-traumatic bone infection in a juvenile-dominated phytosaur (Archosauria; Pseudosuchia) community
The Anatomical Record (advance online publication)
doi: https://doi.org/10.1002/ar.70160
https://anatomypubs.onlinelibrary.wiley.com/doi/10.1002/ar.70160
We report for the first time an epidemic of persistent and recurrent bone infection in a Late Triassic juvenile-dominated phytosaur community. Bone histology of long limb bones and dorsal ribs of nine out of 21 individuals of Colossosuchus techniensis revealed aggressive periosteal growth as represented by distinct crescentic zone(s) of radial fibrolamellar bone tissue in the form of a sunburst pattern of the vascular channels and extensive secondary resorption at the mid- and outer cortical region. We propose that this Colossosuchus community suffered an epigenetic disease influenced by some exogenous factors and/or environments. The possibility of various diseases is reviewed, and within an extant phylogenetic bracketing approach, the most probable cause is inferred to be bacterial infection, especially in the form of osteomyelitis. Alternating occurrences of normal and diseased bone tissue in several limb bones, albeit in several individuals, suggest that the bone infection was persistent and recurrent, and resulted in a suppressed immunodefence system and restricted mobility that ultimately caused the demise of the phytosaur community.
=====
Reply all
Reply to author
Forward
0 new messages