The Geologists Found Evidence of the Oldest Known Fossils of Life on Earth

The Australian and British geologists have found evidence of what may be the oldest-known fossils of life on Earth. The sulfur-based microbes they discovered are 3.4 billion years old. The fossils were very well preserved between the quartz sand grains of the oldest beach known on Earth in some of the oldest sedimentary rocks that can be found anywhere. The bacteria survived on sulfur compounds, which was considered an important transition point as early life on Earth had little or no oxygen to survive on. It might help the search for life on Mars.

The fossils are very clearly preserved showing precise cell-like structures all of a similar size and they look like well known but much newer microfossils from 2 billion years ago; and are not strange or strained in shape or size.  Moreover, they display biological metabolisms. The chemical composition of the tiny fossilised structures is correct, and crystals of pyrite (fool’s gold) associated with the microfossils are very likely to be by-products of the sulphur metabolism of these ancient cells and bacteria.

The finding confirms that life emerged surprisingly shortly after the Earth finished being pulverised by asteroids during the Late Heavy Bombardment, which concluded around 3.8 billion years ago. Only a few hundred million years later – around 3.4 billion years ago – saw the first primitive life emerge, including sulphur-eating bacteria.
The water temperature of the oceans was much higher at 40-50 degrees and circulating currents were very strong.  The landmasses were small at that time, or about the size of the Caribbean islands.