And the tiny village of Pisdura in Maharashtra where this unusual research is being done
You take a jeep from around Warora town, otherwise famous as one of the most polluted in India, and drive 15 odd kilometres, turning into a road which gently rises up for a while into an agglomeration of houses—tiled roofs, mud walls, narrow lanes, men ambling with nothing to do, stray cows, pariah dogs, mild squalor… a village as much as village can get. A retired professor is your guide. He is no longer resident but was born and raised here. So he knows his way around and takes you to fields beyond the village to the other side. That is your destination. The professor keeps inviting men into the jeep, and since they have nothing to do, soon it is a full house. The road levels up, the horizon opens wide, and under the noon sky, the earth is bare and black and brown. You are then on the ground with your group plus the farmers on whose fields you have made yourself guests. You pause to take in the surreality: a bunch of men walking around looking for dinosaur shit. You don’t have a clue what it looks like and at the end of it you still won’t. The others know, and in between there are triumphal shouts. They get some oval stonish pieces, but the professor always exercises a veto—this is too small, that is not it, it could be of something else but is not of a dinosaur. After some time, you concede defeat. Someone says the tailor has one in his collection, but he’s not available. You have had enough anyway.
Your abject failure is the result of your ignorance; it does nothing to Pisdura’s reputation. To palaeontologists, it has always been a trove. “There are sites all around the world where dinosaur fossils like bones, etcetera, are found. But Pisdura is unique in the amount of coprolites found here,” says DM Mohabey of the Geological Survey of India (GSI).
Mohabey is an authority on fossilised excreta—or coprolites. He now works in Lucknow, but used to be director of the GSI’s palaeontology division in Nagpur, the main base to collect samples from Pisdura. One of the highlights in his career has been the discovery of plant remnants in them. “Coprolites had been found before, but there was really none with plant tissues,” he says, “In the late 80s, the GSI took a four-year study to collect coprolites. We collected 250 specimens and they had plant tissues in them. It tells us a lot about the eating habits of sauropods.”
Records of coprolites in Pisdura go as far back as 1860. A 2010 paper in the Geological Society of London, Special Publications, titled ‘The history of dinosaur collecting in central India, 1828-1947’, says of those early finds: ‘…the Reverend Stephen Hislop also collected at Pisdura (Hislop 1860)…Hislop was also the first to observe that most of the fossils were found as surface materials in a nearby field. His collection included vertebrae and a femur from a large dinosaur, in association with a tooth, a fish vertebra, a turtle plastron, and typical Lameta Formation molluscs and coprolites (‘some of them huge enough’…).’
To grasp the reason for such abundance in this region, turn the clock back 65 million years, when dinosaurs (and most other species on earth at the time) went extinct in what is known as the ‘K/T Boundary’ event. A number of reasons are speculated for it—a meteor impact leading to a dust cloud which cut the earth off from sunlight, starvation as a result of an acute food shortage, the possibility that many species adapted and changed forms. In the same period there were also huge volcanoes in the Deccan (which itself might have led to the K/T Extinction, by one theory). Their lava flowed over and over for hundreds of thousands of years, fossilising many surface bodies, including dinosaurs and their droppings. Pisdura is in the Deccan area.
Coprolites are useful because they offer evidence of what dinosaurs consumed. From that, inferences can be drawn of their habitat. “From the remains in coprolites, you can reconstruct or presume the nature of the forest around it,” says palaeobotanist K Ambwani. The evidence in coprolites does not come from just food. Dinosaurs also drank water in which algae and unicellular organisms were present; too small to be digested, these got stuck in food material and were expelled. Also found in these fossils are fungi, either consumed by the dinosaur or which became part of the dropping when it was fresh on the ground and putrefying. Insects too made droppings their home and then died when they dried up. From all this, palaeontologists get an understanding of life as it existed in that period. “By knowing [of] an insect like a honeybee in the coprolite, you can say [something] about the nature of the area. If a honeybee should be there, there must be flowering plants,” says Ambwani.
Two of Ambwani’s studies are interesting. In one, he and his co-researcher Debi Dutta found the presence of some seeds in a coprolite. This particular piece was ‘about 6 cm long, and 4.5 cm broad, greyish in colour, ovoid in shape containing two silicified seedlike structures measuring 2.0 cm in length and 1.5 cm in width’. ‘Based on the shape, size, presence of single cotyledon and lateral position of the embryo,’ they observed, ‘the seeds indicate close resemblance to the phoenicoid group of Arecaceae.’ This, says Ambwani, was nothing but the seeds of the “common khajur palm”. He infers that tall dinosaurs were feeding off palm trees.
Their research led to another paper two years later which showed that smaller dinosaurs, which couldn’t reach that high, were grazing and foraging on the ground. Another coprolite they studied showed the presence of four or five seeds of plants from a family known as Capparidaceae. “The seeds in the coprolite match the modern Capparidaceae in size, shape, their morphology, and are as good as they were present 65 million years ago,” he says, “These plants have fruits which fall down within a month of growing. Those animals that could not reach up the tree might have eaten these fallen fruits.”
Researchers make such deductions by studying the presence of phytoliths, tiny crystalline things present in every plant, in coprolites. “Tear off a grass leaf and put it under a microscope. You can see the small crystals arranged in a whole long row. These are phytoliths,” says Ambwani. By looking into the nature, morphology and geometry of these tiny crystals, you can arrive at the type of plant they belong to.
Ashok Sahni is 71 years old and comes from a family of palaeontologists. It was his grandfather, Ruchi Ram Sahni, who first ventured into this field of science, and Lucknow’s Birbal Sahni Institute of Palaeobotany is named after his uncle. In 2003, Sahni was the co-author of what he calls a landmark paper published in Science magazine that “shed light on the early evolution of grasses and grass-eaters”. This, they deduced from Pisdura’s coprolites. “Grasses were supposed to be a young evolutionary group. When we published [the paper], we took back this whole evolutionary lineage of the grass family to 65 million years ago. That paper had 160 odd citations,” he says. Later, there was an offshoot to this paper published a year ago which showed that dinosaurs may have been rice eaters. Rice, until then, was thought to be of too recent an origin to be part of their diet. “In the initial paper, we had described a ‘family’ [of plants] to which the ‘rice tribe’ belonged. Ultimately, with some more work, we were able to isolate more speci- mens,” he says.
Such studies make it possible to reconstruct how the region must have been millions of years ago. When the dinosaurs roamed, the Deccan was likely a semi arid area with sparse vegetation. It was low lying, with rivers and water bodies. Dinosaurs could survive despite the low vegetation because they were cold-blooded creatures. “We also know that there were crocodiles, turtles and even a snake which ate a dinosaur,” says Mohabey.
Dinosaurs migrated across long distances in an interplay of environments. “It is likely they have eaten green plants, desert plants and aquatic plants also. We are getting the result of the admixture of all this,” says Ambwani. Researchers know that 20 km to the east and south of Pisdura, there must have been a pond or lake because only aquatic fossils are found there. “You don’t get the big plants there,” he says, “Only those which exist in water, very delicate and tiny ones.”
Pisdura is so rich in coprolites because the level at which ploughing is being done for agriculture now is the same at which the droppings got fossilised. There was once a time that scientists could come and go back with loads of coprolites, but now it’s becoming increasingly difficult to find samples. The stock is nearing exhaustion. “You get very few coprolites,” says Ambwani, “In the coming times, you may not get any.” Yet, the search must go on. Sahni says that existing studies of coprolites have only just scratched the surface. “There are undescribed coprolites which have fish scales in them,” he says, “They are obviously related to some meat eater. Pisdura is unique. Even now if you look carefully enough, you will get some specimens, one or two good ones.”
Meanwhile, the village itself is a study in adaptation, being one of the world’s few—or perhaps only—where illiterate farmers are savvy about dinosaur dung. According to some palaeontologists, there even exists a side trade in coprolites. All this is in stark contrast to how the villagers would treat coprolites in the days before scientists arrived in such numbers.
Mohabey remembers an incident from 1999 when he was collecting specimens. He came across a tribal temple where a few bones and some coprolites were stored in a heap. There was one very good specimen and he asked a local if he could take it. The man agreed. But then some villagers turned up and protested. Soon, a big crowd had gathered and the situation was threatening to get out of hand. An exasperated Mohabey finally asked them whether they knew what their object of worship really was. “This is ‘tatti’,” he informed them. Shit. “Their expression changed. One of them picked it up and just flung it into the field.”