The Rajasthan state in western India is home to the hot Thar Desert today. However, during the Mesozoic Era, dinosaurs and other marine life lived there as part of a tropical beachfront along the Tethys Ocean.
A dinosaur group known as the dicraeosaurids, which munched on plant life with long necks (albeit not as long as some of their near cousins), was the source of the most recent discovery from that desert, dating to 167 million years ago. It is the earliest fossil ever discovered in the globe and the first member of its group to be found in India.
Tharosaurus indicus is the name of the species, which was found by an all-Indian team and is named after both its home country and the Thar Desert. They contend that it highlights the need of researching fossils from the Indian subcontinent to more thoroughly comprehend the antiquity of our planet. They announced the discovery earlier this month in the journal Scientific Reports.
Dicraeosaurids, which include Tharosaurus indicus, are classified as diplodocoid sauropods. These dinosaurs are distinguished by having lengthy necks and bodies. They are common throughout the Middle Jurassic to Early Cretaceous eras of fossil beds. The dicraeosaurids, which can be identified by spikes on the back of their necks, have been discovered in China, Africa, and the Americas. However, according to research author and vertebrate palaeontologist Sunil Bajpai of the Indian Institute of Technology Roorkee, no such fossils have ever been identified in India. Previous hypotheses postulated that only the ancestors of diplodocoids lived in India.
However, Dr. Bajpai and other scientists questioned whether there was more to the tale. A partnership between the Geological Survey of India and IIT Roorkee was launched in 2018 with the goal of methodically locating and excavating fossils close to Jaisalmer, a significant city in the Thar Desert. Initial discoveries included marine bony fish and now-extinct hybodont sharks. Then, in 2019, work on dinosaur fossil excavation began, leading to the identification of Tharosaurus indicus.
The scientists have named this newly discovered dinosaur species as #TharosaurusIndicus. They had long necks and elongated bodies. This is a pioneering discovery in #BharatRashtra,— BHĀRAT RĀSHTRA (@BHARAT__RASHTRA) August 20, 2023
Thar desert was a coastline to the Tethys Ocean, back then, that was inhabited by these herbivores. pic.twitter.com/U6k5vQVoWJ
With extended depressions on the sides of its neck bones, neural spines with deep divisions that may have resembled upward spikes on its neck, and a heart-shaped front surface on its tail bones, the dinosaur stood apart from other members of its group. It also supports a different theory on the existence of sauropods in what is now India.
“It represents the earliest global record of not only dicraeosaurids but also of diplodocoids,” said Debajit Datta, a co-author of the paper and a postdoctoral earth sciences researcher at IIT Roorkee.
Together with other primitive dinosaur discoveries from the Early Jurassic Kota Formation in central India, such as Barapasaurus and Kotasaurus, the discovery of Tharosaurus strongly suggests that what is now India played an important role in the emergence and diversification of neosauropods, a group of long-necked vegetarian dinosaurs that thrived as the largest land animals. This finding is reinforced by the configuration of continents during the Middle Jurassic period, according to Dr. Datta.
Dr. Bajpai also cited further findings that showed the Indian subcontinent had a significant role in the creation and evolutionary development of other vertebrate groupings. Examples are the remains of Indohyus and Cambaytherium, which were significant in determining the evolutionary history of horses and whales, respectively.
Andrej Eransk, a vertebrate palaeontologist at Comenius University in Bratislava, Slovakia, stated, “We still do not know very much about the past of India. Therefore, discoveries like this new fossil are essential to our knowledge because they provide key details regarding the history of the subcontinent’s paleogeography and the development of its creatures.
Even though India is home to priceless fossils from many eras, according to Dr. Bajpai, there aren’t enough vertebrate palaeontologists to fully investigate them. According to him, access to some fossil locations is restricted due to mining operations, deep forest cover, a lack of finance, and a lack of available employment prospects.
However, he expressed optimism that new government recommendations will aid in the preservation and protection of significant fossil sites as well as other geoheritage sites around the nation.