World's Oldest Fossils Are Not Actually Fossils, New Research Suggests

Two years ago, researchers from the University of Wollongong in Australia shook the world by claiming to have discovered 3.7 billion-year-old fossils in a rock formation in Greenland, a finding that pushed back the origin of life on Earth by 200 million years . New research is now casting doubt with this discovery, with scientists saying the rock structures are of non-biological origin.

In the original 2016 study, Allen Nutman geologist and colleagues identified cone-like structures, ranging between 1 and 4 centimeters in length, in 3.7-billion-year-old rock found in the Isua Formation in southwest Greenland. These structures, the researchers said, were evidence of stromatolite-sedimentary formations created by the layered growth of microbial bodies in shallow waters. At the time, it was considered the oldest evidence of life on earth, demonstrating the rapidity of life after the formation of our planet some 4 billion years ago. The most important things in the world today.

The apparent stromatolites have been identified in badly deformed "metamorphic" rocks, which have been heated, twisted, crushed, and contorted over the vastness of geologic time. Despite this, Nutman's team said they were able to see the signs of sedimentary history within the rocks, including the alleged stromatolites. No organic compounds or biomarkers (so-called "chemical fossils") were found, but the conical-shaped structures and finely layered textures were interpreted as remnants of ancient microbial life. At the same time, Nutman ruled out other possibilities, such as weirdly folded rock.

Skeptical of these findings, Abigail C. Allwood, a geologist from the California Institute of Technology, Minik T. Rosing, a geochemist at the University of Copenhagen, and colleagues at the Isua formation in Greenland Themselves. Their resulting analysis, published today in Nature, suggests Nutman and his colleagues got it wrong. The observed structures in the rocks are just products of tectonic processes, they say, and there is absolutely nothing biological about them.

Nutman, despite these claims, is standing by his work, saying Allwood and Rosing have failed to discredit his team's analysis. Meanwhile, another researcher not involved Both teams have insufficiently proven their points, and that the search for the planet's oldest microbial fossils continues.

For the new research, Allwood and Rosing analyzed the three-dimensional shapes, positions, and chemical composition of the rocks purported to contain the fossils. The formations in the interior of the body are of organic microbial life, they say, and they do not contain any organics or chemical evidence of biological life.

What's more, a new 3D perspective of the structures suggests they're not even conical in shape-they're actually ridge-shaped, according to the new analysis. Cuts made to the rock "show that the stromatolites" are not cones or elongate cones, but ridges extending at least 10 cm (our sampling depth) into the rock, aligned with the lengthening direction, "the researchers write in the study. "The ridges probably extend further, given the extreme elongation of the rock fabric observed in the outcrop."

Accordingly, Allwood and Rosing "proposes that none of the previously published results support the interpretation of the [Isua] Structures as stromatolites. "The rock formations are non-biological in nature, the researchers say, interpreting the" structures as structural deformation and carbonate alteration of layered rock. "But if there's anything Nutman, Allwood, and Rosing do agree on, it's been created in a marine environment.

Gizmodo reaches out to Nutman for how to make it clear that he is unimpressed with the attempted takedown of his team's research.

Among all of them are Allwood and her fellow students at the Isua training in Greenland, and they are there. He said that a "Greenland government observer" who waited Allwood's expedition said it was a "short one-day helicopter trip," and that the scientists avoided the site (outcrop B) explored by Nutman because it was "covered by a thin layer of snow, "choosing a different, more accessible site (outcrop A) instead. "Unlike us, they did not extensively review the relationships with the geology of the outcrops," he told Gizmodo. Nutman said he was "mystified" that Allwood and her colleagues focused on the end of the site, which, because of its severe tectonic deformations and chemical weathering, was observed in this particular part of the rock formation.

"This is a classic comparing apples and oranges scenario, leading to the inevitable outcome that bears and their observations do not exactly match," Nutman told Gizmodo. "Allwood never took up the offer of our sample, so they could make an independent assessment of the best-preserved original specimens."

Nutman argued that all of them were out of favor, and that all of them had not been able to do this. As an example, these stromatolites were only seen at the center of rock folds, where smaller degrees of deformation allow for the preservation of "primary structures" within the rocks.

As for Allwood and the claim that tectonic compression has been produced, Nutman said this interpretation "completely fails to explain" why the bottom of the stromatolite struc- ture structures are flat and irregular. "This is not how layered rocks like those at the local stromatolite behave in tectonic compression," he said. Allwood's team claims the rock structures are not internally layered, "but this is not true," said Nutman. "Indeed, the stromatolite structures we showed do contain vestiges of layering."

Based on these and other issues, Nutman said, "We are extremely rare stromatolites in the Isua rocks, preserved in a tiny relict of a 3.7 billion year old shallow sea environment."

"I think that the evidence is way remains very thin."

Dominic Papineau, a geochemist from the University College London who was not involved in this study, was not impressed with the re-analysis or the original paper, saying "the evidence is way remains very thin."

The Nutman paper introduced the possibility of the fossil rocks containing fossils, but Papineau said Allwood and Rosing failed to perform their own due diligence on the matter.

"There was no systematic analysis of the microscopic fabric, mineral assemblages, and of the possible presence of graphite (from metamorphosed biomass) and its composition in these unusual rocks," Papineau told Gizmodo. "This new work is not advancing any of these important aspects, but it is important to assess the possible geobiological origin, but are almost entirely undocumented."

A big issue that Papineau has with the paper is that Allwood and Rosing failed to perform a comparative analysis of rocks that were more or less than the samples studied. If they looked at older rocks, for example, and they were able to show consistent processes, they would have had more evidence to strengthen their case, he said .

For example, Papineau said this interpretation "lacks support from younger stromatolite-like rocks in similarly deformed" outcrops. Like Nutman, Papineau is questioning both the samples used and not used in the new analysis.

Ultimately, Papineau said the jury is still out on the matter, as he feels Nutman's paper "was not compelling." Part of the problem, he said, has been due to the challenges of identifying microbial life in such ancient, tortured rocks.

"Papineau told Gizmodo," Papineau told Gizmodo, "This is difficult because of the range of experiences. "The biggest challenge remains the ability to generate data sets with multiple independent techniques, with their own limitations and data representation, to obtain multiple independent lines of evidence."

Papineau himself is very much invested in this line of research. In March 2017, he published 3.7 million-year-old canadian rock.