the first evidence of primitive cellular life was the 1977 discovery of microbial fossils in the swartkoppie chert, a type of granular sedimentary rock rich in silica. why is this evidence not considered definitive? multiple choice objects that look like cells can be formed by geological forces as the rocks formed. there was no evidence of water, therefore it is questionable whether cells could have been present. the fossils did not look like bacterial cells. there is no evidence of carbon dioxide, which is needed to prove that living organisms respired.