Fossils Point to Life on Earth 4 Billion Years Ago

And Dr Dominic Papineau, also from UCL, who discovered the fossils in Quebec, thinks this kind of setting was very probably also the cradle for lifeforms between 3.77 and 4.28 billion years ago (the upper and lower age estimates for the NSB rocks).

UCL’s Matthew Dodd said the tiny fossils – half the width of a human hair and up to half a millimetre in length – lived near a vent in the seafloor where water was heated by a volcano. Those are believed to have formed near hydrothermal vents that gushed super-hot water laden with minerals.

Lead co-author Michael Dodd of University College London (England) said the discovery could lead scientists to new clues about how life on Earth and other planets emerged.

These tubes from hydrothermal vent deposits may represent the oldest microfossils and evidence for life on Earth.

Researchers digging in a remote area of Quebec, Canada have unearthed 3.8 billion-year-old fossils, which may point to how life got started on earth. In a new study, scientists studying 3.77-billion-year-old rocks have found tubelike fossils similar to structures found at hydrothermal vents, which host thriving biological communities.

The new study is just the latest to determine that the Red Planet may have contained habitats with the potential to support life.

Tiny tubes and filaments in some Canadian rock may be the oldest known fossils. If similar signs of life are found on Mars it might suggest that life, in some form or another, is a lot more common in the Solar System than first thought. The type of rock that the belt is made of – a layered blend of basalt and chert – can only be dated by using a method that is less accurate than the one used to date a section of continental crust in the Northwest Territories thought to be about as old. Sometime in those early years it’s believed another large chunk of space rock slammed into the planet and rebounded into orbit, where it eventually became the moon. “If life happened so quickly on Earth then could we expect it to be a simple process and start on other planets, or was Earth really just a special case?”

The researchers, led by University College London and including scientists from Norway, the US, Australia, Canada and the United Kingdom, believe the rock belt in Canada originally was part of a thermal vent system. Scientists examining the chemical makeup of some of the Earth’s oldest rocks, located in northwestern Canada, may have found the oldest-known chemical fossils of bacteria.

“On the basis of chemical and morphological lines of evidence, the tubes and filaments are best explained as remains of iron-metabolizing filamentous bacteria, and therefore represent the oldest life forms recognized on Earth”, the Nature paper concludes. They also contain a level of carbon indicative of a living organism. In other words, life could not have been hardy from the get go.

The worldwide team used a laser imaging system, ion beams, and electron miscroscopes to look at the structures in the rock – not just their shape but the minerals they were made of.

Boswell Wing, a University of Colorado geobiologist who has also studied the Nuvvuagittuq belt, was less convinced.

RG: How does this finding fit into the known timeline life on Earth? . It’s the oldest physical evidence of life on this Earth – found in Canada’s Arctic.

Moreover, the flower-like quartz structures in which the tubes and filaments are embedded have often been found in younger rock to contain traces of bacteria that consumed iron for energy.

The finding makes it considerably more likely that life has existed on Mars – where the key ingredient of liquid water arrived at about the same time as it did on Earth – and elsewhere.