Animal life on Earth may be 1.5 billion years older than we thought: new research

Life on Earth looks good for its age.

Newly discovered fossil records hint that single-celled, mold-like organisms—the common ancestor of all complex life on our planet—arrived over a billion years earlier than previously estimated.

The evidence was found deep in rock formations within the African nation of Gabon with abundant fossils suggesting conditions for animal life began around 2.1 billion years ago, the BBC reported.

Going back 3.7 billion years, the first traces of life consist of microbial bacteria that lack a nucleus, while it is widely accepted that animal organisms began as recently as 635 million years ago. However, new findings challenge this theory.

These primordial life forms, slithering, single-celled organisms that would “move” to move and reproduce by spores, were discovered in a landlocked body of water, indicating that early life forms never spread globally. However, their spread “set the stage” for the animal kingdom to evolve before they became extinct, the researchers write in a new report published in the journal Precambrian Research.

Cardiff University professor Ernest Chi told BBC News, “We’re saying, look, here are fossils, there’s oxygen, it’s stimulated the emergence of the first complex living organisms.”

“We see the same process as in the Cambrian period, 635 million years ago – that helps. This helps us finally understand where we all came from,” he added.

The chemistry of the rock in which the fossil was found points to a “laboratory” of life-producing elements. Chi believes that a continental collision and subsequent volcanic activity would have created the “nutrient-rich shallow marine inland sea” in which photosynthesis could initiate oxygen production.

“This would have provided enough energy to drive increases in body size and more complex behaviors observed in primitive, simple animal-like life forms such as those found in fossils from this period,” he said.

However, some not involved in the research are skeptical.

“I’m not against the idea that there were higher nutrients 2.1 billion years ago, but I’m not convinced that this could lead to diversification to form complex life,” said Professor Graham Shields of University College London.

Other neutral parties give the idea more of a fighting chance.

A candidate at London’s Natural History Museum, Elias Rugen agreed that the building blocks of life “were all doing something a little bit unprecedented at this point in Earth’s history”.

“There is nothing to say that complex biological life could not have emerged and flourished by 2 billion years ago.”