Scientists identify the oldest forms of life

Some of the oldest forms of life, confirmed to be 3.5 billion years-old, have been identified by a team of researchers at the University of Queensland.

The UQ team, led by School of Physical Sciences scientists Dr Miryam Glikson and Associate Professor Sue Golding, as well as Associate Professor Lindsay Sly from the School of Molecular and Microbial Sciences, are the first to conclusively confirm the nature and source of the organic material.

"What we have found is the first visual confirmation of primitive microbial communities in what is considered to be the best preserved ancient organic matter on our planet," said Glikson.

"We used difficult and time-consuming electron microscope techniques to conclusively confirm the microbial remains," Golding said.

"The integration of observational and micro-analytical techniques is unique to our approach."

The remains were found in some of the oldest preserved organic matter on Earth, obtained from core drilling samples from Western Australia's Pilbara region.

"The Pilbara region is such a good research site, as it has ancient forms of the white smokers active at plate margins today and black sulfidic smokers found in sea floor vent systems in tectonically active sites," said Golding.

"These are the places where scientists believe life on Earth might have had its origins."

Glikson said the team then took the study further, by comparing the fossil microbial structures to primitive microbes found in sea floor environments, similar to those existing 3.5 billion years ago.

"The microbiologists on the team, led by Dr Sly, cultured currently existing primitive microbes under simulated conditions to those of the ancient forms of life," said Glikson.

"A remarkable resemblance was found between the structures of the cultured microbial entities at their stage of disintegration and those of the ancient microbial remains."

A comparison with organic matter from rocks of similar age in South Africa also yielded microbial remains identical to those from the Pilbara, further confirming the research.

Aspects of the research have been published in the prestigious scientific journal Precambrian Research.