London, Oct 13 (ANI): London, Oct 13 (ANI): Scientists have discovered tiny tubes that have been etched into South African rocks by microbes at least at least 3.3 billion years ago, and believe that the tubules could represent the earliest 'trace' evidence of activity by microbes on Earth.
Researchers at University of Bergen analysed the material filling the structures, which indicated that they were created not long after the volcanic rock itself was spewed on to the seafloor.
"We're kind of looking at their 'footprints' - we're looking at the holes, the microborings, left by the bugs as they dissolved into, or chewed, into the rocks," the BBC quoted Dr Nicola McLoughlin University of Bergen as saying.
"But things get more difficult in the ancient [setting] because the shapes are simpler and the chemistry has been modified. What this paper does show, however, is the progress we have made in dating these structures," she added.
The structures are seen in rocks from the famous Barberton Greenstone Belt in the Mpumalanga Province of South Africa.
The constant recycling of rock means there are very few locations like Barberton where a physical record of the ancient Earth can still be examined.
This geochemical signal is also supported by shapes and textures - so-called trace fossils - in the rock, which could have been cut by the ancient microbes.
At the very least, this type of investigation will researchers more about what conditions were like on Earth almost 3.5 billion years ago.
The dating work is reported in Earth and Planetary Science Letters. (ANI)