Origin of life on Earth not a mystery anymore

 Origin of life on Earth : 1.75billion years old code cracked

Small truth about photosynthesis aids scientists in solving mystery behind Earth's life origin. Researchers on a quest to understand the origins of life just learned a little lesson about photosynthesis from 1.75 billion years ago. In a new study published in Nature, a team of researchers claim that microfossils found in the desert of north Australia show off the earliest known signs of photosynthesis. And that could means a better understanding of how all of life could have begun. Microfossils discovered exhibit the earliest known evidence of photosynthesis, which might lead to a deeper comprehension of the possible origins of life itself as per Popular Mechanics.

These microfossils are remnants of a type of organism called cyanobacteria, which experts believe have been around for as long as 3.5 billion years (though the oldest confirmed fossil examples are from about 2 billion years ago). At some point in their evolution, some varieties of these organisms developed thylakoids, structures within cells in which photosynthesis occurs, which may have allowed them to contribute huge amounts of oxygen to Earth’s atmosphere through photosynthesis in what has become known as the Great Oxidation Event. Some of these species may have been able to contribute enormous amounts of oxygen to Earth's atmosphere through photosynthesis during the Great Oxidation Event because, at some point in their evolution, they developed thylakoids.

The earliest evidence of photosynthesis discovered to date is provided by these new findings. According to the researchers, these earliest photosynthesising cells formed some 1.75 billion years ago, and their discovery extends the fossil record by at least 1.2 billion years. “[This discovery] allows the unambiguous identification of early oxygenic photosynthesisers and a new redox proxy for probing early Earth ecosystems,” the authors wrote, “highlighting the importance of examining the ultrastructure of fossil cells to decipher their paleobiology and early evolution.” 

These new findings offer up the oldest evidence of photosynthesis found to date. The researchers claim that these very first photosynthesizing cells appeared roughly 1.75 billion years ago. These exciting fossils were discovered in ancient rocks, located in the McDermott Formation in northern Australia, and feature the pigment chlorophyll, which allows organisms to absorb the sunlight during photosynthesis. The presences of chlorophyll was enough for researchers to determine that photosynthesis had occurred in these little compartments, which would mean that the process evolved much earlier than was previously demonstrable.

This would likely help explain the Great Oxidation Event. Evidence in the fossil record shows us that there was a huge jump in atmospheric oxygen levels around 2.4 billion years ago. It was critical to the existence of life on Earth as we know it, and while scientists aren’t sure what caused it, one theory is that this is around the time that photosynthetic organisms evolved into being and began to exist in large numbers. By dating fossilized cells with the necessary components for photosynthesis to as close to that oxygen-flourishing event as possible, researchers are able to move one step closer to understanding the role of oxygen, and the cells helping create it, in the origins of life on Earth. Of course, the next step is more research. Specifically, the team intends to examine fossil cells across the world to see just how well they match up with this new timeline.