How did life appear on Earth? What caused the emergence of life in its earliest and primordial forms? Why did life evolve in such an extraordinary diversity of millions of species of animals and plants? Are we the outcome of the Primordial Soup, Panspermia or did some divine being create us all? Why do we exist at all? Such questions had baffled the minds and greatly stimulated the curiosity of scientists, philosophers and priests worldwide for thousands of years.
The stromatolites may have the answer
The UNSW researchers found exceptionally preserved microbial remnants in some of Earth’s oldest rocks in Western Australia, which are named stromatolites – fossilized microbial structures.
The stromatolites have been discovered in the ’80s and scientists always had the hunch that they are of biogenic origin, but the theory was initially refuted until now. The journal Geology published yesterday, September 26th, the opposite claim, meaning that stromatolites do are of biogenic origin.
Lead researcher Dr Raphael Baumgartner, a research associate of the Australian Centre for Astrobiology in Professor Martin Van Kranendonk’s team at UNSW, says: “This is an exciting discovery – for the first time, we’re able to show the world that these stromatolites are definitive evidence for the earliest life on Earth,”
Optional research needed
“Unfortunately, there is a climate of mistrust of textural biosignatures in the research community. Hence, the origin of the stromatolites in the Dresser Formation has been a hotly debated topic,” Dr Baumgartner says.
“In this study, I spent a lot of time in the lab, using micro-analytical techniques to look very closely at the rock samples, to prove our theory once and for all.”
Dr Baumgartner analyzed the rocks from the Dresser Formation where stromatolites are dwelling, by using a variety of cutting-edge micro-analytical tools and techniques – including high-powered electron microscopy, spectroscopy and isotope analysis.
“The organic matter that we found preserved within pyrite of the stromatolites is exciting – we’re looking at exceptionally preserved coherent filaments and strands that are typically remains of microbial biofilms,” Dr Baumgartner says.
Are the stromatolites the earliest forms of life on Earth? Science may irrefutably answer this question in the future, but all we know for sure is that the microbial structures represent a good candidate for the title. Probably the next big step in science is to find out where stromatolites came from.