3.4 Billion Year Old Fossils Discovered In Australia

Scientists digging through sandstone in Western Australia have discovered evidence of cellular life from a time when Earth didn’t even have an oxygen atmosphere:

A team of Australian and British geologists have discovered fossilized, single-cell organisms that are 3.4 billion years old and that the scientists say are the oldest known fossils on earth.

Their assertion, if sustained, confirms the view that life evolved on earth surprisingly soon after the Late Heavy Bombardment, a reign of destruction in which waves of asteroids slammed into the primitive planet, heating the surface to molten rock and boiling the oceans into an incandescent mist. The bombardment, which ended around 3.85 billion years ago, would have sterilized the earth’s surface of any incipient life.

The claim is also a new volley in a long-running conflict over who has found the oldest fossil.

The new microfossils are described in Sunday’s issue of Nature Geoscience by a team led by David Wacey of the University of Western Australia and Martin D. Brasier of the University of Oxford. The fossils were found in sandstone at the base of the Strelley Pool rock formation in Western Australia.

The sandstone, 3.4 billion years ago, was a beach on one of the few islands that had started to appear above the ocean’s surface. Conditions were very different from those of today. The moon orbited far closer to earth, raising huge tides. The atmosphere was full of methane, since plants had not yet evolved to provide oxygen, and greenhouse warming from the methane had heated the oceans to the temperature of a hot bath.

It was in these conditions, the geologists believe, that organisms resembling today’s bacteria lived in the crevices between the pebbles on the beach. Examining thin slices of rock under the microscope, they have found structures that look like living cells, some in clusters that seem to show cell division.

Cell-like structures in ancient rocks can be deceiving — many have turned out to be artifacts formed by nonbiological processes. In this case, the geologists have gathered considerable circumstantial evidence that the structures they see are biological. With an advanced new technique, they have analyzed the composition of very small spots within the cell-like structures. “We can see carbon, sulfur, nitrogen and phosphorus, all within the cell walls,” Dr. Brasier said.

Crystals of fool’s gold, an iron-sulfur mineral, lie next to the microfossils and indicate that the organisms, in the absence of oxygen, fed off sulfur compounds, Dr. Brasier and his colleagues say.

If sustained, then we’re talking about not only the oldest known record of life on Earth, but also evidence that life, at least on a microscopic level, can indeed survive in a hostile environment without the presence of oxygen. The implications of that finding for studies of the stars should be rather obvious.

 

 

 

FILED UNDER: Quick Takes, Science & Technology
Doug Mataconis
About Doug Mataconis
Doug holds a B.A. in Political Science from Rutgers University and J.D. from George Mason University School of Law. He joined the staff of OTB in May 2010 and contributed a staggering 16,483 posts before his retirement in January 2020.

Comments

  1. OzarkHillbilly says:

    It is just a plant by the devil to fool the gullible into thinking the planet is older than the 6,000 years that it really is

  2. Boyd says:

    Out of all the rocks in the world, how did they ever decide which ones to look at? That’s amazing!

  3. Neil Hudelson says:

    3.4 Billion Year Old 6.000 year old Fossils Discovered In Australia

    FTFY

  4. Tea Party Patriot! says:

    I hate Rick Perry thread in 3…..2…..1……

  5. Michael says:

    @Boyd:

    Out of all the rocks in the world, how did they ever decide which ones to look at? That’s amazing!

    A bunch of scientists were sitting around pondering where they could find a 3.5 billion year old fossil, when someone finally said “I know! Let’s try looking in those 3.5 billion year old rocks!”.

  6. Boyd says:

    @Michael: Maybe it’s all easier than it seems to me to be, since everything I know about geology I learned from The Flintstones (the prime time version).

    It’s just that I’ve never seen a “use by” date on a rock (or a “born on” date if we want to follow the beer model), so it seems like you’d have to go through a lot of rocks to get to the right ones.

  7. Michael says:

    It’s just that I’ve never seen a “use by” date on a rock (or a “born on” date if we want to follow the beer model), so it seems like you’d have to go through a lot of rocks to get to the right ones.

    Geologists have had a lot of time to document some of the oldest rock formations. Usually it’s a matter of “how far below the surface is it”. Think of the Grand Canyon, the rocks in the walls at the bottom of the canyon will be known to be older than those at the top. So when you’re looking for really old fossils, you just need to know where the very deep rocks can be found.

  8. Michael says:

    Of course, just as soon as I post that and go to find information about the Strelley Pool rock formation (and after having to skip past 3.4 billion articles about the recent find), it appears to not be very deep at all, but rather just a very flat but geologically stagnant area in Australia.

    The point remains though, that scientists generally know where to look for old rocks.

  9. Drew says:

    Helen Thomas is in Australia?

  10. OzarkHillbilly says:

    Helen Thomas is in Australia?

    It looks like Helen Thomas….

  11. Tano says:

    evidence that life, at least on a microscopic level, can indeed survive in a hostile environment without the presence of oxygen

    This is hardly some great revelation, Doug. There is free oxygen in the atmosphere precisely because living matter released it through the photosynthetic process. If there were no life before an oxygenated atmosphere, there would never have been any accumulation of oxygen in the atmosphere. We have known this for a long time now.

  12. Ben Wolf says:

    It is just a plant by the devil to fool the gullible . . .

    This is a ridiculous statement. Everyone knows the jews planted those rocks in 1924, not the devil.

  13. george says:

    This is a ridiculous statement. Everyone knows the jews planted those rocks in 1924, not the devil.

    That’s an obvious attempt at misdirection. But it won’t work, we all know it was the Masons.