Life, as we know it today, is vastly different from the life in primeval Earth that had no oxygen yet. It was at a point of early planetary evolution. At this stage, the primordial soup of life needed a form of nourishment. Before oxygen, arsenic keeps life going until the following stage.

Move back a billion years in the past, and the Earth around you will not be the same as it is today. It was similar to an alien world just at the cusp of starting life. An enigma that has not been revealed yet. Arsenic, which is deadly to most life now, might play an important role in sustaining earlier life forms.

Evidence suggests that the primordial stuff is what simple creatures had for nourishment. They even exist until now, according to Meaww.

The key to life before the existence of oxygen in early Earth is the formation of arsenic in the elements. Think of it as a midway crutch to find something to support primordial life. Breathing and making food which made simple microbes a biological success, based on a recent study.

The lead of the study is Dr. Pieter Visscher, who gave his insights into the nature of this phenomenon. He proposes for half of the Earth's existence in the universe, the young planet doesn't have oxygen yet. Characterizing life on this proto environment are large slimy mats of microbes living in shallow liquid, cited Phys org.

During the the interview, Dr. Visscher, Dr. Brendan Paul, and Kimberley L Gallagher stated that these simple mats of microbial organisms lived with oxygen. The next question is what sustained their existence in a highly toxic environment. What did they do to survive in such extreme conditions?

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Researchers wondered how unlikely compounds consisting of iron, sulfur, hydrogen kept life going in such pre-existing conditions. To date, there's a large gap in fossil records because the proof is not available yet. In the early cauldrons of life, that was just a still pool in a proto landscape with bare amounts of it. Next is that iron, sulfur, nor hydrogen can be the answer, but arsenic.

The scientist did a prior study based on the hypothesis that ancient microbial lifeforms sustained by arsenic. Proof were obtained by getting clues from limestone rocks that are a product of bacteria called stromatolites.

The source of this archaic evidence was obtained when they drilled into a 2.72-billion-year-old stromatolite, an ancient reef in the Australian outback. The examination of the drilled samples revealed two types of arsenic. No trace of iron or sulfur when the rock was formed in antiquity.

Despite the impact of the discovery of ancient earth conditions, the researchers said in The Conversation that they looked for an equivalent which is microbial mats as further proof. They added that these microbial mats cannot be seen in an oxygen-free environment. If it is ever found, then it shows how ancient stromatolites came to be in a world without oxygen. This what differentiates Earth from a proto world with no oxygen.

Visscher stated that after studying microbial mats for 35 years, the bottom of the stream is deep purple an indication of microbial mat communities. It bears a similarity to the primordial soup in a pre-oxygen supported life.

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