The secrets of a world-renowned fossil treasure have been revealed by cutting-edge technology and could provide important clues about the origins of life on Earth.
Scientists believe their analysis of a 400-million-year-old hoard discovered in a remote area of north-east Scotland shows better molecular preservation of fossils than previously thought.
Researchers have been able to determine the chemical signatures of many of the creatures present in the amazingly well-preserved hoard from Aberdeenshire.
Just as the Rosetta Stone helped Egyptologists translate hieroglyphs, the team hopes these chemical codes will help them decipher more about the identity of life forms represented by other, more ambiguous fossils.
A spectacular fossil ecosystem near the village of Rhynie in Aberdeenshire was discovered in 1912, mineralized and encased in chert – a hard rock composed of silica. Known as the Rhynie chert, it dates back to the Early Devonian period – about 407 million years ago – and plays a significant role in scientists’ understanding of life on Earth.
Scientists have combined the latest in non-destructive imaging with data analysis and machine learning to analyze fossils from collections at National Museums Scotland and the Universities of Aberdeen and Oxford. Researchers from the University of Edinburgh have been able to probe deeper than previously possible, which they say could reveal new insights into less well-preserved specimens.
Using a technique known as FTIR spectroscopy – in which infrared light is used to collect high-resolution data – the researchers discovered an impressive preservation of molecular information in cells, tissues and organisms in the rock.
Since they already knew which organisms represented the majority of fossils, the team was able to discover molecular fingerprints that reliably distinguish between fungi, bacteria and other groups.
These prints were then used to identify some of the more enigmatic members of the Rhynia ecosystem, including two specimens of a mysterious tubular “nematophyte”.
Found in Devonian and later Silurian sediments, these strange organisms have characteristics of both algae and fungi, and were previously difficult to place in either category. The new findings suggest they are unlikely to be lichens or fungi.
Dr Sean McMahon, Chancellor’s Fellow for Physics and Astronomy and the University of Edinburgh’s School of GeoSciences, said: “We have shown how a rapid, non-invasive method can be used to distinguish between different life forms, and this opens a unique window. on the diversity of early life on Earth.”
The team fed their data into a machine learning algorithm that was able to classify different organisms and provided the potential for sorting other datasets from other fossil rocks.
The study, published in Nature Communications, was funded by the Royal Society, Wallonia-Brussels International and the National Science and Technology Council of Mexico.
Dr Corentin Loron, Royal Society Newton International Fellow from the University of Edinburgh’s School of Physics and Astronomy said the study shows the value of linking palaeontology with physics and chemistry to generate new insights into early life.
“Our work highlights the unique scientific importance of some of Scotland’s spectacular natural heritage and provides us with a tool to study life in more complex and ambiguous remains,” said Dr Loron.
Dr. Nick Fraser, Curator of Natural Sciences at National Museums Scotland, believes that the value of museum collections to understanding our world should never be underestimated. He said:
“Continued developments in analytical techniques provide new avenues to explore the past. Our new study provides another way to look ever deeper into the fossil record.
