Published on February 3, 2021
Ahmedabad: A team of researchers that carefully dug through 1,500kg of fossiliferous rock at Tapar and Pashuda villages near Anjar in Kutch district, were rewarded with proverbial chuhiyas (rats). These were no simple rodents though, as the samples opened a new chapter of the late Miocene age with the remains dating back to 10 million years ago.
The paper ‘First Miocene rodents from Kutch, western India’ by Ansuya Bhandari from Lucknow-based Birbal Sahni Institute of Palaeosciences (BSIP), published recently in the journal ‘Historical Biology’, throws light on nine species of murines/murids or old-world rats found in the Indian peninsula for the first time. The study was done with Dr Lawrence Flynn of Harvard University.
The study highlights that the region had murines, primitive bamboo rats, chipmunks and other rodents from the late Miocene period.
Earlier, similar species were reported from the Shivalik range in Pakistan. The team also claimed to find a new species, indicating regional differentiation.
Analysis of fossilized teeth revealed a variety of rodents. Dr Bhandari said the discovery is important from multiple aspects. “It gives us a peek into the biodiversity at this spot 10 million years ago, also giving us the oldest age to find the rodents. These are the first recorded Miocene rodents outside the Siwalik, extending the southern range of its discovery,” she said.
Earlier, remains of apes, horses, rhinos, elephants among other animals have been found from the region. “I have worked in the region earlier – starting in 2010 – and we were successful in finding evidence of Miocene age fossils that led us to discoveries such as Sivapithecus (ape), hipparion (primitive horse), pigs, rhinos, elephants, giraffids, bats, turtles and anthracotheres (extinct hippo-like mammals) among others. Thus, we were encouraged to search further,” said Dr Bhandari, who is associated with the Vertebrate Palaeontology Lab of BSIP.
The researchers pointed out that the small teeth of fossilized rodents tell a big story. According to their hypothesis, the region was not arid as today and had a subtropical ecosystem and moist environment, if not dense forest. “Of course, we cannot compare today’s rats or mice directly with these species, but for understanding’s sake, we can say that they were almost of the same size today. They were grazers and may have seeds and leaves in their diet,” she said.
Progonomys morganae, an index fossil, has been recorded for the first time in India, the researchers said.