The origin of life has been widely debated and theorized about throughout history. Scientists now know that the Earth is 4.2 billion years old and the only system we know that can support life -- specifically for human beings -- due to its plate tectonics, liquid water on the surface, and the oxygen in our atmosphere. However, this was not always how the earth looked as detailed by ancient rocks that immortalize key aspects of Earth's evolution.
These ancient rocks have provided humans with concrete facts about the creation of Earth, and Tara Djokic, an astrobiologist and PhD candidate at the Australian Centre for Astrobiology of the University of New South Wales Australia, recently discovered an ancient rock in the Western Australian desert that provides an alternative explanation for the origin of life -- in the form of simple, microscopic bacteria -- that dates back 3.5 billion years. Prior to her discovery, rocks dating back to this period were nearly impossible to locate due to destruction and deformation caused by the plate tectonics.
Not only does Djokic's discovery confirm a new timeline for life on Earth, but it also suggests that life evolved on land in hot springs, not in the ocean as previously thought. Hot springs contain hot water and dissolving minerals from the surrounding rocks that are mixed with organic compounds to produce a "chemical factory" that created simple cellular structures that are the backbone of life.
This new clue in the creation of life may shift our understanding of humanity, and while the origin of life on Earth will never be 100% certain, this discovery suggests that intelligent life takes approximately 4 billion years to evolve.