Life on Earth originated 3.75 billion years ago – 300 million years EARLIER than previously thought

The first life on Earth appeared at least 3.75 billion years ago – about 300 million years earlier than previously thought, a new study has revealed.

The revelation is based on analysis of a stone the size of a fist from Quebec, Canada, which is estimated to be between 3.75 and 4.28 billion years old.

Researchers had previously found tiny filaments, buds and tubes in the rock, which appeared to be made of bacteria. However, not all researchers agreed that these structures were of biological origin.

Now, after extensive further analysis, the team at University College London has discovered a much larger and more complex structure inside the rock – a stalk with parallel branches on one side that is almost an inch long.

They also found hundreds of distorted spheres or ‘ellipsoids’ next to the tubes and filaments.

The researchers say that although some of the structures could have been created through random chemical reactions, the ‘tree-like’ stem with parallel branches was most likely of biological origin.

This is because no structure created via chemistry alone has been found similar to it.

Until now, the earliest known evidence of life on Earth was a 3.46 billion-year-old rock from Western Australia containing microscopic worm-like fossils.

Dr. Dominic Papineau holds a sample of the rock, estimated to be between 3.75 and 4.28 billion years old

Pictured: The ‘woody’ stalk with parallel branches on one side, considered to be the most compelling trace of life in the rocks. The main stem begins at the bottom left and extends upwards almost to the top of the image, with ‘pectinate’ (parallel aligned on one side) branches on the right side of the stem.

How the research was conducted

Researchers studied rocks from Quebec’s Nuvvuagittuq Supracrustal Belt (NSB), once part of the ocean floor and containing some of the oldest sedimentary rocks known on Earth.

The research team cut the rock into sections about as thick as paper (100 microns) using a diamond-coated saw, to closely observe the tiny fossil-like structures made of hematite, a form of iron oxide or rust, and encapsulated in quartz.

They then compared the structures and compositions with newer fossils as well as with iron-oxidizing bacteria located near hydrothermal vents today.

This allowed them to identify contemporary equivalents to the twisted filaments, parallel branched structures, and distorted spheres (irregular ellipsoids), for example, near the Loihi submarine volcano near Hawaii, as well as other venting systems in the Arctic and Indian Oceans.

“Using a wide variety of evidence, our study strongly suggests that a variety of types of bacteria existed on Earth between 3.75 and 4.28 billion years ago,” said lead author Dr. Dominic Papineau from UCL’s Department of Geosciences.

“This means that life could have begun as little as 300 million years after the formation of the Earth. In geological terms, this is fast – around a spin of the Sun around the galaxy. ‘

The team also revealed evidence of how the bacteria got their energy in different ways.

They found mineralized chemical by-products in the rock, which are consistent with old microbes that feed on iron, sulfur and possibly also carbon dioxide and light through a form of photosynthesis that does not involve oxygen.

These new findings suggest that a variety of microbial lives may have existed on the original Earth.

They also have implications for the possibility of extraterrestrial life.

“If life is relatively fast to emerge, given the right conditions, this increases the chance that there is life on other planets,” said Dr. Papineau.

For the study, the researchers examined stones from Quebec’s Nuvvuagittuq Supracrustal Belt (NSB), collected by Dr. Papineau in 2008.

NSB, once part of the seabed, contains some of the oldest sedimentary rocks known on Earth, believed to have been laid down near a system of hydrothermal vents where cracks in the seabed escape through iron-rich water heated by magma.

Clear red concretion of hematic chert (an iron-rich and silica-rich rock), which contains tubular and filamentous microfossils

Clear red concretion of hematic chert (an iron-rich and silica-rich rock), which contains tubular and filamentous microfossils

Dr.  Dominic Papineau in his lab at UCL.  The new results suggest that a variety of microbial lives may have existed on the original Earth

Dr. Dominic Papineau in his lab at UCL. The new results suggest that a variety of microbial lives may have existed on the original Earth

The research team cut the rock into sections about as thick as paper (100 microns) to closely observe the tiny fossil-like structures made of hematite, a form of iron oxide or rust, and encapsulated in quartz.

These cutting discs, cut with a diamond-coated saw, were more than twice as thick as previous sections that the researchers had cut, allowing the team to see larger hematite structures in them.

They compared the structures and compositions with newer fossils, as well as with iron-oxidizing bacteria located near hydrothermal vents today.

This allowed them to identify contemporary equivalents to the twisted filaments, parallel branched structures, and distorted spheres (irregular ellipsoids), for example, near the Loihi submarine volcano near Hawaii, as well as other venting systems in the Arctic and Indian Oceans.

For the study, the researchers examined stones from Quebec's Nuvvuagittuq Supracrustal Belt (NSB), collected by Dr.  Papineau in 2008

For the study, the researchers examined stones from Quebec’s Nuvvuagittuq Supracrustal Belt (NSB), collected by Dr. Papineau in 2008

In addition to analyzing the sample samples under various optical and Raman microscopes (which measure the scattering of light), the research team also digitally recreated sections of the clip using a supercomputer that processed thousands of images from two high-resolution image processing techniques.

The first technique was micro-CT or microtomography, which uses X-rays to look at the hematite inside the rocks.

The other was focused ion beam, which shaves small – 200 nanometer thick – slices of stone, with an integrated electron microscope that takes a picture between each slice.

Both techniques produced stacks of images that were used to create 3D models of different dimensions.

The 3D models then allowed the researchers to confirm that the hematite filaments were wavy and twisted and contained organic carbon, which are properties shared with today’s iron-eating microbes.

In their analysis, the team concluded that the hematite structures could not have been created through squeezing and warming of the rock (metamorphosis) over billions of years.

They pointed out that the structures appeared to be better preserved in finer quartz (less affected by metamorphosis) than in the coarser quartz (which has undergone more metamorphosis).

The researchers also looked at the levels of rare earth elements in the fossil-laden rock and found that they had the same levels as other ancient rock samples.

This confirmed that the seabed deposits were as old as the surrounding volcanic rocks, and not younger ‘fraud infiltrations’ as some have suggested.

Prior to this discovery, the oldest fossils previously reported were found in Western Australia and dated to 3.46 billion years old, although some scientists have also disputed their status as fossils, claiming that they are of non-biological origin. .

HOW IMPORTANT IS PHOSPHORUS FOR LIFE ON EARTH, AND HOW DID IT BECOME HERE?

Although not nearly as abundant on Earth as carbon, hydrogen or oxygen, phosphorus is one of the key elements in the life of our planet.

It helps to form the backbone of the long chains of nucleotides that make up the DNA building blocks of biological life as we know it.

Phosphorus is also essential for cell membranes and the cell-carrying molecule ATP.

Phosphorus probably came to Earth aboard meteorites billions of years ago.

The meteorites are thought to have contained a phosphorus-containing mineral called schreibersite.

Researchers recently developed a synthetic version of schreibersite that chemically reacts with organic molecules, demonstrating its potential as a nutrient for life.

Leave a Comment