Complex Life May Have Started on Earth Much Earlier Than We Thought

All life on Earth probably came from one spark. It diversified, branching off into different groups that helped it survive.

New research suggests that the steps may have taken place earlier than previously thought, which is a point of contention in the scientific community.

The University College London researchers built on the evidence of diverse life inside a fist-sized piece of rock from Quebec in Canada.

The structures in the rock were thought to have been left by ancientbacteria.

The structures that would push the first signs of life on Earth back by at least 300 million years were not believed to be biological.

The stem-like structures are the oldest known fossils.

The team discovered a larger and more complex structure after further analysis of the rock. A stem-like structure with parallel branches on one side that are nearly a centimeter long was found within the rock.

Life could have begun as little as 300 million years after Earth was formed. The lead author of the study says that this is about one spin of the Sun around the galaxy.

The key question was whether it was possible for these structures to be formed through chemical reactions not related to living things.

According to the paper, some of the smaller structures could have been the product of abiotic reactions, however, the newly identified tree-like stem is most likely biological in origin, as no structure like it, created through chemical reactions alone, has been found before.

Researchers found chemicals in the rock that could have been from different types of metabolism.

The chemicals are consistent with energy-extraction processes in the bacteria that would have involved iron and sulfur; depending on the interpretation of chemical signatures, there could even be hints of a version of photosynthesis.

It is possible that the early Earth was inhabited by an array of life.

The rock was analyzed through a combination of optical observations and a computer that processed thousands of images from two high-resolution techniques.

The piece of rock was collected in 2008 from the Nuvvuagittuq Supracrustal Belt, which was once a part of the seafloor. Some of the oldest rocks on Earth can be found in the NSB. Researchers found that the rock had the same levels of rare Earth elements as other ancient rock samples, and that it was as old as the surrounding volcanic rocks.

The rock is bright red and contains microfossils. D. Papineau.

The earliest fossil evidence of life was found in Western Australia, which dates back 3.46 billion years. There is a contention about whether the fossils were biological in origin.

What it means for the potential distribution of life in the Universe is one of the most exciting implications from this discovery. If life was able to evolve in the harsh conditions of the very early Earth, then it may be more common throughout the universe.

The authors of the paper state that this discovery implies that only a few hundred million years are needed for life to evolve to an organized level.

The oldest microfossils and dubiofossils reported here from the NSB suggest that extraterrestrial life may be more widespread than previously thought.

The journal Science Advances published the study.