Millions of years before humans walked the Earth, a giant long-legged dinosaur roamed the Indian subcontinent. But what connects Rabindranath Tagore to this 185-million-year-old creature?
At the Geology Museum inside the Indian Statistical Institute (ISI), Kolkata, stands the fossil of Barapasaurus tagorei — one of the earliest known sauropods, named in honour of the Nobel laureate.
The dinosaur species comes from the lower part of the Kota Formation of Pranhita-Godavari valley dating back to the Early Jurassic Period. It is reported to be one of the earliest known sauropods — the long-necked, long-tailed herbivorous dinosaurs with small heads and thick, pillar-like legs.
Vertebrate palaeontologist Debarati Mukherjee, assistant professor at the Geological Studies Unit (GSU) of ISI Kolkata, said the fossil bones were discovered in a heterolithic unit of red clay and sandstone from the lower Kota Formation of Pranhita-Godavari valley along the border districts of Maharashtra and Telangana. All known fossil bones of Barapasaurus come from localities near the village of Pochampally.
The first signs of the fossils — portions protruding from the host rock — were spotted by scientists from GSU, ISI, during a geological field trip in 1958. However, systematic scientific excavation began only in 1961 and continued till 1964. Second excavation followed in 1961-62 near Krishnapur village in the Adilabad district of present-day Andhra Pradesh, while a third excavation was carried out in 1964 at Sironcha.
“After spotting the surface indications, time was needed to prepare for systematic excavation, and the preparation itself took a couple of years,” Mukherjee said.
Interestingly, the first fossil excavated was a 1.2-metre-long thigh bone or femur.
According to Mukherjee, a driver accompanying the field team remarked, “Arrey sahab ye toh bohot bara pao wala janwar hai” (Sir, this is an animal with a huge leg). The dinosaur was subsequently named Barapasaurus, meaning a “large-legged lizard”.
The species name “tagorei” was chosen in honour of Rabindranath Tagore because the systematic excavation began in 1961, the poet’s birth centenary year. Mukherjee noted that ISI founder Prasanta Chandra Mahalanobis shared a close association with Tagore, which also inspired the tribute.
Around 300 bones were excavated from the site, representing at least six individuals belonging to different age groups. As a result, Barapasaurus is one of the most completely known Early Jurassic sauropods, with almost the entire skeleton recovered except for the anterior cervical vertebrae and the skull.
Transporting the fossils to Kolkata and mounting the skeleton was a massive undertaking. While the excavation ended in 1964, the mounting process continued until 1977, taking nearly 13 years to complete. It became the first mounted dinosaur skeleton in Asia.
Scientists painstakingly identified the placement of each bone, though the original skull could not be recovered because skull fossils are extremely fragile. The skull currently displayed is therefore a scientific replica of a Diplodocus skull.
The excavation itself was equally meticulous and required massive energy support. Overlying mudstone layers were carefully removed, and each fossil bone was uncovered using pointed steel tools and brushes. To prevent damage, the fossils were wrapped in plaster-of-Paris bandages.
Once brought back to the laboratory, the fossils underwent extensive preparation and osteological study, ultimately revealing a previously unknown Jurassic sauropod dinosaur from India.
Though considered an early and relatively unspecialised sauropod, Barapasaurus shows the building plan typical for later, more derived sauropods. Mukherjee noted that the vertebral column already shows many traits that are more developed in later sauropods.
The excavation team in 1961 was led by Professor P. L. Robinson of University College London, alongside Tapan Kumar RoyChowdhury, Dr. S. L. Jain and T. S. Kutty of ISI Kolkata.
Scientists believe a catastrophic flood may have killed the herd of Barapasaurus. Their carcasses were likely transported by floodwaters, while uprooted tree logs accumulated the decomposed and disarticulated bones at one location.
Mukherjee added that naming species after literary or cultural icons is not uncommon in science. “This bridges the gap between history, science and culture, while also piquing people’s curiosity,” she said.
The Geology Museum at ISI Kolkata, maintained by Mukherjee and associate professor Shiladri Sekhar Das, is unique for its collection of fossils ranging from the Permian to Neogene periods, with a special emphasis on the diversity of Gondwana fauna.
The museum is open to visitors, especially students, from Monday to Friday (11.30am to 5pm) except public holidays, though interested visitors must send a request email (geologymuseum@isical.ac.in) to the authorities at least 24 hours in advance before planning a visit.