India and Australia were evolutionary neighbors, a link found in Bhimbetka’s broadcasts

Bhimbetka, the famous central Indian rock art repository near Bhopal dating from the Paleolithic and Mesolithic times, has yielded a fossil find dating from around 550 million years ago, the first time the organism fossilized particular has been registered in India. It dates back to an era considered to be the forerunner of the explosion of life on earth during the Cambrian Period and places India firmly on the map of Ediacaran era studies along with Australia and Russia. Here’s what makes this discovery a global milestone:

India’s first Dickinsonia

The recent discovery of the very first fossils of the organism Dickinsonia by a team of researchers led by Gregory J. Retallack reported in the journal Gondwana Research has excited scientists studying the evolution of some of the first living species over a period of the history of the land known as the Ediacaran, named after the Ediacara Hills in South Australia.

That period in Earth’s history, where Dickinsonia and several multicellular organisms existed, was approximately 635 million years (Ma) and 541 Ma ago, with the living creatures of the time called vendobionts. Previously, Dickinsonia fossils have been found in Russia and Australia, among others. They extend up to a size of even a meter. The earliest Indian fossils were found in the cave roof of the Bhimbetka rock shelters auditorium, preserved in the Maihar sandstone of the Bhander group, which is part of the rocks of the Vindhyan subgroup. The research was reported late last year.

Proximity to Australia

The age of fossil rocks is determined using isotopes. Zircon dating of the youngest Maihar sandstone in Madhya Pradesh puts its age at 548 Ma, while the lower Bhander group in the Son and Chambal valleys gave an isotope-derived age for limestones ranging from 978 Ma to 1073 Ma, locating it in the old Tonian end point. The Ediacaran period was the forerunner of the Cambrian (c. 541 Ma to 485.4 Ma) when the earth witnessed an explosion of life forms, much of which constitutes modern animal life today.

Age profiles of Dickinsonia fossils in Maihar sandstone, determined using Zircon dating, make them comparable to those in the Russian White Sea region, at around 555 Ma. Further evidence comes from Comparable fossils of Dickinsonia tenuis and Dickinsonia costata in South Australia, estimated at 550 Ma. Studies of the characteristics of rocks in and around Bhimbetka show that they shared several characteristics with rocks in Australia, including the texture of ” old elephant skin ”and also a trace of the fossil, Prasinema gracile, notes the research paper.

Scientists discovered that Dickinsonia fossils from India were identical to Rawnsley quartzite in South Australia, proving their age and the proximity of the two landmasses of Gondwanaland at that time. However, the evidence did not support the reconstructions adjusted for the polar wandering phenomenon. [which involves motion of continents over geologic time and its impacts].

A distinctive feature of these creatures is the absence of hard protective parts such as skeletons and (outer) shells, possibly because there were no predators. It was also the time when evidence shows some of the earliest multicellular organisms, or metazoans. The evidence comes from life forms in the water when the earth lacked life.

Sailor, animal or other?

From an evolutionary standpoint, the discovery of Dickinsonia and other Ediacaran species such as Ernietta and Arumberia, as the team led by Retallack discusses, raises the question of whether they were marine organisms. shallow or non-marine in nature. Noting the remote locations of the fossil finds separated by deep oceans and the Dickinsonia cluster in Australia-India and the Baltic, the researchers propose that these could have been in an environment similar to ancient geological times, rather than in a single biogeographic province.

Whether Dickinsonia is an animal or another organism has been a matter of different interpretation, a group of researchers led by Ilya Bobrovskiy arguing that their discovery of cholesteroids in preserved material using lipid biomarkers, reported that it they were indeed animals. Retallack and his colleagues claim that such cholesterols are also found in red algae and most fungi. Knowledge of Ediacaran biogeography is evolving, and India today is a theater for studies of life on earth at a time when the subcontinent was in a different place on the globe.