It's possible that whales and horses originated in India
IIT-Roorkee’s Sunil Bajpai, who has spent 35 years collecting fossils and piecing together their history, believes that many mammals originated in India
Roorkee—All around us are objects millions of years old yet well-preserved and neatly displayed in glass cases. We are inside the geological museum in Roorkee’s Indian Institute of Technology that houses rare fossils from around the world, the oldest ones dating back an unbelievable 65 million years.
Among the museum’s prized possessions are the skulls of a 42-million-year-old whale and a 20-million-year-old sea cow from Kutch, the thigh bone of a 2-5-million-year-old elephant, a meteorite from Argentina, manganese nodules found 5km beneath the Arabian Sea, amethyst crystals from Brazil, and limestone specimens from the top of Mount Everest.
Short walk away, we meet Professor Sunil Bajpai, the head of Department of Earth Sciences at IIT Roorkee. In his office-laboratory are thousands more such fossils. Sensing our amazement, he starts by explaining that the need for such a museum in an engineering institution is to expose students to the all-encompassing world of earth sciences. The museum is named after the Irish geologist and professor Henry Benedict Medlicott, who worked in India in the mid-19th century.
For the past 35 years, Bajpai has been collecting fossils from around the world, and today, the museum, which was opened about three years ago, has a collection of semi-precious crystals and rocks from India and abroad. “I started collecting fossils in 1986 and my collection comprises large and small-sized ones. Nearly 2,000 large fossils are catalogued in my vertebrate paleontology lab here,” he says.
Most of the fossils in his collection are from the Surat and Kutch regions of Gujarat, with some from the Himalayas. The oldest fossils, including those of a whale and a sea cow, date back 65 million years, but on average, his collection covers a period between 15 and 55 million years ago, a period when the earth went from being super-hot to cooling down through a series of ice ages.
A geologist with research interests in vertebrate palaeontology, Bajpai is the former director of Birbal Sahni Institute of Palaeosciences in Lucknow and is credited with conclusively establishing that India was the centre of the evolution of many groups of modern mammalian life, particularly whales, horses and primates.
He and his team make frequent visits in search of fossils to Gujarat, Madhya Pradesh (Dhar, Chhindwara, Jabalpur, Mandla), Rajasthan (Jaisalmer) and the Himalayas. What’s needed is a keen eye for the right kind of rocks and any indication of the presence of fossils.
“These indications may be broken pieces that are actually hard body parts such as bones and teeth. If we find a fragmentary fossil that is only partly visible on the rock surface, we dig very carefully using hammer and chisel to ensure it is not destroyed,” Bajpai explained. Once carefully transported to his lab, the fossils are cleaned for examination and identification. The lab has both optical microscopes as well as scanning electron microscope to study minute fossil details. Together they’ve published papers is some of the world’s best known scientific journals, including Nature.
The team is presently studying 20 million-year-old fossils from Kerala, 55 million-year-old fossils discovered in coal mines in Kutch and Rajasthan, and 65 million-year old fossils from Madhya Pradesh and Gujarat.
“One of the best specimens I found in a huge limestone block was a 42 million-year-old skull of a fossil whale. It was well preserved but bringing that huge limestone block here was not easy. Another time I was delighted to find a beautifully preserved skull of a 20 million-year-old sea cow in Kutch. I forgot all about the Kutch’s harsh climate at that moment when I found the skull,” Bajpai recalls.
Bajpai’s careful digs have unearthed evidence to indicate that the whales swimming our oceans today had their origins in India. He’s also used fossil remains to establish the discovery of a family of most primitive early horses, cambaytheres (about 55 million years old). His team excavated the fossils in the coal mines of Vatsan in Surat, indicating that modern-day horses too originated in India.
At Vatsan, they also found fossils of early primates dating back 55 million years. This is the group to which humans and apes trace their orgins, again, strongly suggesting that India was the major centre of evolution and diversification of present-day mammals. “All these discoveries have put India on the world map of fossils, and highlight the importance of our country as the centre of origin or early evolution of several groups of modern mammalian life,” says Bajpai.
In the Himalaya, the team found hundreds of well-preserved skulls, limbs and teeth of Indohyus, a land mammal from about 50 million years ago, which eventually made its way to the sea. Together, the fossils from the Himalaya and Kutch tell us how these creatures moved from land to sea and how their organ systems—for everything from locomotion and hearing to balance and feeding—changed during migration from land to marine environments.
“We have also discovered and identified a variety of sea cow fossils (marine herbivorous mammals that feed on sea grass) in Kutch. These fossils tell us that abundant sea cows lived in the Indian Ocean about 15-20 million years ago. The fossils, including beautifully preserved skulls, have been described as new forms such as Kutchisiren, Domningia, Bharatisiren, as they were not known previously,” explains Bajpai.
It bothers Bajpai that there’s little effort and no laws to govern excavation, protection and conservation of fossils in India. “Although serious efforts have been initiated in the past 2-3 years by geoscientists and palaeontologists as well as the government, this needs to be done with the utmost sense of urgency to save our fossil faunas and floras from being destroyed.”
Bajpai believes these fossils are a window to the past as well as the future. They tell the fascinating story of the evolution of life since its origin nearly 3,500 million years ago, besides providing critical insights into ecosystems. But funding for such research is dependent solely on the Department of Science and Technology, Council of Scientific & Industrial Research and the Ministry of Earth Sciences.
“Fossil data are critical for supporting or refuting molecular (DNA) data on the evolutionary history of modern life forms. It provides the much-needed data on age, environment and correlation of rocks in which fossils are found,” he says. And for those wanting economic reasoning for investment such excavation, Bajpai has it: “Such data are vital for studies related to petroleum exploration.”
But more importantly, learning about the Earth’s past geography, such as the distribution of land and sea, provides insights the rate of change of past climates and its possible consequences. “All of which is extremely important in understanding the causes and consequences of the present-day climate change and future trends,” he says.
FIRST PUBLISHED01.04.2021 | 07:00 AM IST