although several older texts use the term Vindhyas to cover them (see Historical definitions above). Geology and palaeontology The "Vindhyan Supergroup" is one of the largest and thickest sedimentary successions in the world. The earliest known multicellular fossils of eukaryotes (filamentous algae) have been discovered from Vindhya basin dating back to 1.6 to 1.7 billion years ago. Shelled creatures are documented to have first evolved at the start of the Cambrian 'explosion of life', about 550 million years ago. See also Geology of India Geology of the Himalayas References Mountain ranges of India Ancient Indian mountains Geography of Malwa Landforms of Madhya Pradesh Geography of Ujjain Mountains in Buddhism