Large number of shark teeth found at Rajasthan’s fossil site
A large number of shark teeth have been found at a new fossil site in Rajasthan’s Barmer district, the study of which has provided valuable insight about the environmental changes in the region from warm, humid, coastal conditions to the present-day dry and desert-like climatic condition.
The research by the University of Delhi’s geology department was recently published in the Geobios journal. “To fill the fossil gap between Cretaceous to Eocene epoch, our team conducted a field investigation in the Barmer district which led to the discovery of a new fossil site known as Padma Rao open cast quarry located 40 kilometres from Barmer city and 3 kilometres south of Giral Lignite mine. A large number of shark teeth belonging to various sharks - namely Squatiscyllium nigeriensis, Ginglymostoma sokotoense, among others - were recovered from this site,” research leader Dr Priyadarshini Rajkumari said.
After comparing the recovered fossils with other fossil found from Fatehgarh formation, Kapurdi formation and Akli formation in western Rajasthan, the experts found that the palaeoenvironment and palaeoecology of this new fossil site were different from the other fossil sites.
Most of the fossil record from other fossil localities were deposited in coastal lagoonal environment with frequent marine and freshwater inputs. But the newly discovered fossil site lacks terrestrial and freshwater fauna as compared to the other fossil localities within Barmer district.
“This could be possibly due to the different depositional environment and slightly older in age of the studied area which has been suggested as late Paplaeocene age based on the present fauna,” she added.
“Most of the sharks teeth recovered from this fossil site are mainly found in nearshore shallow marine environment restricted to inner shelf area. The shark fossil from the Padma Rao quarry indicates the presence of tropical to sub-tropical climate during the deposition of fuller’s earth deposits of the Padma Rao quarry. The study of these shark teeth gave us an insight about the environmental changes from warm, humid, coastal conditions to the present-day conditions of dry and desertic climatic condition in the region,” the research paper stated.
According to the research paper, one of the important findings is that the shark fossil recovered from the Padma Rao quarry also shows similarities with fossils which were found in the African region (Morocco, Nigeria and Niger), Western Europe (Belgium, England and France), North America and Asia, indicating that the fauna may have utilized the Tethys seaway as a migration route between these regions during the late Palaeocene.