| Details: |
The advent of simple unicellular life forms on the earth from the primordial soup and its evolution into complex multicellular forms is intriguing. One needs definitive evidence to understand the processes and timelines of this transformation. Simple unicellular life forms continued for ~2 billion years in the earth's history evolved into cells with nuclei and subsequently transformed into complex multicellular forms. Today all the advanced life forms are invariably constituted of eukaryotic cells. The time and reason for the advent of nucleated cell complexity are not well understood. Experimentalists and theorists need crucial evidence in the form of the body-fossils to discuss the physical principles underlying shaping the cooperative dynamical behaviour and selective pressures. Fossils entombed in the rock records provide unequivocal evidence.
With the availability of some of the oldest rocks, a prerequisite for such studies, the Indian subcontinent is the ideal natural laboratory to test the different models and hypotheses related to the origin of life. Cratonic parts of India have provided crucial evidence of the evolution of the early life forms. The discovery of stromatolites, also known as organosedimentary structures, is indirect yet, definitive evidence of biological activity in Archaean. The Cuddapah, Kaladgi, Vindhyan, Chhattisgarh, Bhima, Marwar, and Krol basins distributed across the country are part of the Proterozoic sedimentary successions of India (2500-541 million years old). These sedimentary successions have revealed megascopic prokaryotic forms, eukaryotic cellular remains, acritarchs, benthic seaweeds, Vase Shaped Microfossils (VSM), and varied stromatolites.
Collectively all these advancements in Precambrian Palaeobiology in the Post-Darwin era are discussed. The present talk deliberates on the documentation and results of the detailed investigation made on the Indian Precambrian basins and chronicles the importance of Indian palaeobiological evidence in our understanding of the early evolution of life on the earth.
|