Dawn | December 20, 2010 Baluchitherium: The largest land mammal

by Suhail Yusuf

Click image for additional photos and original Dawn.com story.

After the dramatic extinction of the dinosaurs, the bones of the largest land mammal were discovered in 1910 by English paleontologist Sir Clive Forster Cooper. In Balochistan, Cooper discovered bones of extra ordinary size. He suggested that the mammal was the size of a dinosaur and named it as Baluchitherium or "˜the beast of Balochistan'. But for almost a century, the creature remained an enigma because no further investigation was carried out.

In the early 1990s, eminent French paleontologist Jean-Loup Welcomme set out on a journey towards Balochistan in order to find the fossils of the mysterious creature. He followed the footsteps of Cooper and finally discovered that Dera Bugti was the place where Cooper had first unearthed the bones of Baluchitherium. Welcomme came to Pakistan under a project named, "Mission Paleontologique Française au Balochistan". Pakistan Museum of Natural History was another stakeholder in that project.

Welcomme contacted Nawab Akber Khan Bugti and told him the story of that spectacular discovery. Bugti not only gave him the permission for further excavations but helped him with every day needs and workers. In 1997, Welcomme discovered the first finger of the Baluchitherium in a stony valley near Dera Bugti.

The giant of the hidden valley

After the first clue, Welcomme and other mammalian experts unearthed an array of amazing fossils. The team discovered uncountable fossils in a mere 200 square meter area, which could be considered the best exposed bone-beds on Earth. They found many remains of male and female Baluchitherium simply lying on the ground, which was a quite rare event in paleontological findings. Perhaps the massive creatures were swept away by a river and had accumulated on the banks. Scientists also found traces of crocodile's teeth on bones which suggested that the Baluchitherium was also a common prey of crocodiles.

In 2003, the French team carefully examined every major and minor bone and finally put them in proper place, building a composite skeleton of the Baluchitherium. The skeleton suggested that the giant creature was five-meters tall and weighed 20 tonnes, almost as massive as the size of three large elephants!

Scientists got the rough idea of the Baluchitherium's height by examining its bones. But defining the mass of any extinct mammal is a tricky job. Teeth and especially bones are very helpful to identify the mass of any mammal. Over decades of investigations, scientists have devised many techniques to find the mass of a mammal by looking at the length and diameter of its bones. These methods can be successfully applied to assess the bone-mass relation of the mammals.

In the geological time scale, Baluchitherium roamed Asia in Oligocene epoch or 30 millions years ago. According to plate tectonics, some 200 million years ago, the sub-continent was locked - it was a part of the great Gondwanaland which comprised South-America, Africa, Sub-Continent and Australia.

This block had been dismantled into parts and slowly moved towards Asia. 55 million years ago, one part of the Indian plate hit the Asian plate and 43 million years ago the contact between the two was complete. This collision brought about the Great Himalayan Mountains. The Indian-Asian plate collision changed the whole climate of the region.

Heavy rains and erosion turned Balochistan into a lush green rainforest like today's Amazon. The conditions were suitable for a hornless rhinoceros or Baluchitherium to flourish. The lush forest provided enough vegetation for the bulk-eater mammal to survive. Baluchitherium lived for 11 million years, nearly 35 to 24 million years ago.

After working on the Baluchitherium, Welcomme tried to uncover the entire environment it shared. The team discovered the diversified fossils of fish, turtles, crocodiles, rodents and other small mammals. He studied 40 sites that described 12 distinct levels of different geological ages. He also discovered prehistoric trees, flowers and leaves.

Amazingly, the team found shark teeth, fish and shells which suggested that around 32 million years ago an epicontinental sea had appeared in the heart of Balochistan, which was a rare phenomenon.

Is Balochistan a cradle for humanity?

Prehistoric Balochistan can also be considered an exact place of migration of mammals coming from South East Asia on the road to Africa or Europe. Simply put, it could be called a cross road for African mammals. Amazing fossils of ancestors of elephants and lemurs also discovered in Balochistan, strengthened the hypothesis that many animal groups have Asian origins. We can assume that this place was an evolutionary highway for the kin of today's many advanced animals. Surprisingly the French team discovered some 20,000 fossils of mammals only from and around the areas of Dera Bugti.

Two important discoveries are worth mention here, one is the mystery of lemur. Bug-eyed and slow moving lemurs now only live on the island of Madagascar. Before 2001, scientists had believed that only Africa was the birthplace of lemurs. But a lemur fossil discovered in Pakistan changed the paleontology text books.

Laurent Marivaux, another French expert discovered a 30 million-year-old fossil of a lemur from Balochistan. Dubbed as Bugtilemur Mathesoni, it is now the oldest fossil of lemur found anywhere on the planet. Bugtilemur triggered a new debate among scientists that lemurs may have Asian rather than African roots.

The details of that discovery were published in the prestigious research journal, "Science", in which Marivaux said, "The discovery was totally unexpected and the time has come for the Asian scenario to receive more serious attention."

Gifted writer, Nigel Calder, wrote in his book: "By the boldest interpretations of genetic geography, modern humans may have emerged in South-central Asia- perhaps somewhere east or southeast of the Caspian Sea on the Kazakhstan-Balochistan axis-because that is where the indigenous populations are most "intermediate" between genetic extremes of Africa, Australia, and the Americas." Time Scale: page 58

The evidence of the above statement came from other finding of Jean Loup Welcomme. He discovered another fossil valley called "Paali" in Balochistan.

On a very hot day in Paali, he filled his clear plastic bags with sand. Back to the small lab in a Dera Bugti guest house, he washed and screened the sand and was surprised that the grains were so little that the screen was empty except for some dark grains. But, later, under the microscope, he realised that those grains were in fact the teeth of small-sized mammals which had remained well preserved. Among them was a tooth of a primate!

Thus Paali became a window to our own group - Anthropoid Primates. Afterward, more teeth of primates discovered from the same site suggested that Balochistan could be the motherland of all animal groups including humans. But further excavation is needed to find more astonishing results because scientists have been screening other areas for decades but only five per cent of Dera Bugti searched so far. It is important to unearth Balochistan's paleontology scenario, because its open fossil beds are ready to reveal the treasure to the whole world. For instance, only Paali area holds the secret of more than 10 million years of ancient life on the planet.

Why did the Baluchitherium become extinct?

The answer lies in the same conditions which developed a stage for Baluchitherium to flourish. Some 22 million years ago, the movements of Asia and Africa destroyed the most important prehistoric sea, the "Tethys". The disappearance of the sea gradually changed the climate of Asia. Balochistan turned into stony desert from a green valley. The vegetation disappeared and Baluchitherium became extinct in the battle of survival.

Fortunately, Nawab Akber Khan Bugti kept the Baluchitherium bones in 10 metallic containers. After he was killed, the fossils were recovered and sent to the museum of the Geological Survey of Pakistan and still remain there.

Pakistan is an "˜El Dorado' for fossil hunters. However, serious attention is also required to highlight the discoveries from Pakistan. It has been a decade since the complete skeleton of the largest land mammal was discovered from Pakistan. Beautiful series of postal tickets could be issued or the Baluchitherium could be declared the symbol of Balochistan.

A veteran artist, Asim Mirza, beautifully carved a one-tenth scale model of the Baluchitherium. He also invited Jean Loup Welcomme to see how it looked.

When Welcomme first saw the fiber glass model, he was amazed to see the authenticity of the prehistoric giant. By his own resources, Mirza has also been working on a life model of Baluchitherium for the past five years and is now on the verge of completing it.

Fortunately, Jean Loup Welcomme will again visit Pakistan in Spring 2011, to work on a joint project with the Sindh University.