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Avascular necrosis: occurrence in diving cretaceous mosasaurs
Science (New York, N.Y.)
|April 3, 1987
Summary
Giant marine lizards, or mosasaurs, commonly had avascular necrosis, a bone disease, in their vertebrae. This condition was absent in some genera, suggesting varied diving behaviors and habitats among these extinct reptiles.
Area of Science:
- Paleontology
- Vertebrate Paleontology
- Paleopathology
Background:
- Mosasaurs were apex marine predators during the Late Cretaceous period.
- Fossilized vertebrae provide insights into the health and biology of extinct species.
- Avascular necrosis is a bone disease caused by interrupted blood supply.
Purpose of the Study:
- To investigate the prevalence of avascular necrosis in extinct mosasaur genera.
- To explore potential ecological factors influencing the occurrence of this bone disease.
Main Methods:
- Macroscopic and histological examination of fossilized mosasaur vertebrae.
- Comparative analysis of avascular necrosis presence across different mosasaur genera (Platecarpus, Tylosaurus, Clidastes).
Main Results:
- Avascular necrosis was present in 5-66% of vertebrae in Platecarpus and Tylosaurus.
- This bone disease was notably absent in the studied Clidastes specimens.
- Differential occurrence suggests genus-specific susceptibility or exposure.
Conclusions:
- The prevalence of avascular necrosis in mosasaurs may be linked to decompression syndrome.
- Habitat and diving behaviors likely differed between mosasaur genera, influencing disease occurrence.
- This study highlights the value of paleopathology in reconstructing extinct animal ecology.
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