Fungal microfossils dating back 635 MILLION are found in China and may have helped Earth recover from the catastrophic Ice Age by boosting marine bioproductivity
- The oldest terrestrial fossil was found in China and dates back to 635 million years ago
- This fungal microorganism is believed to help the Earth recover from an Ice Age
- Experts say it worked with other terrestrial microbes to recover
- Together, they chemically accelerated again and supplied phosphorus to the oceans, boosting the bioproductivity of the sea
It was previously believed that fungi emerged some 240 million years ago, but a new discovery has rewritten the timeline for when the spore-producing organisms first colonized Earth.
An international team of scientists discovered a 635-million-year-old fungal microfossil – making it the oldest terrestrial fossil ever – in rock cavities in southern China.
Researchers say it evolved during the Ediacaran period, when the planet emerged from a catastrophic Ice Age and the microorganism may have played a key role in its recovery.
Along with other terrestrial microbes, the fungus-like organism had the ability to chemically accelerate again and deliver phosphorus to the oceans, boosting marine bioproductivity.
An international team of scientists discovered a 635 million year old fungal microfossil – making it the oldest terrestrial fossil ever – in rock cavities in southern China
The fossil was discovered in well-studied sedimentary dolostone rocks of southern China’s lower Doushantuo Formation by scientists at Virginia Tech, the Chinese Academy of Sciences, Guizhou Education University, and University of Cincinnati.
Tian Gan, a visiting Ph.D. student in the Xiao lab, said, “It was an accidental discovery.”
‘It was then that we realized that this could be the fossil that scientists had long been looking for.
“If our interpretation is correct, it will be useful to understand paleoclimate change and the evolution of early life.”
The fossil was discovered in well-studied sedimentary dolostone rocks of the lower Doushantuo Formation in southern China
The preserved fossil has multiple orders of branches, curved filaments (shown) and ladder-like branching systems
The preserved fossil has multiple orders of branches, curved filaments, and ladder-like branching systems.
When the Ice Age hit the planet, it froze ocean surfaces to a depth of more than a mile, and the environment was so harsh that no organism could survive.
Earth recovered, producing a biosphere that was larger and more complex than before, which was a mystery to scientists – but the new fossil may eventually solve the puzzle.
Researchers believe that the fungal microorganism and other similar microorganisms help restore the environment and did so with the help of their formidable digestive system.
Fungi have digestive systems capable of circulating vital nutrients and can chemically break down rocks and other tough matter with the help of enzymes that are excreted into the environment – all of which can then be recycled and exported to the ocean.
“Fungi have a mutualistic relationship with the roots of plants, which allows them to mobilize minerals, such as phosphorus,” Gan said.
Fungi have digestive systems capable of circulating vital nutrients and can chemically break down rocks and other tough matter with the help of enzymes that are excreted into the environment – all of which can be recycled and exported to the ocean (pictured is a computer image of the fossil)
“Because of their connection with land plants and important feeding cycles, terrestrial fungi have a driving influence on biochemical weathering, the global biogeochemical cycle and ecological interactions.”
Previous work has suggested that terrestrial plants and fungi formed a symbiotic relationship about 400 million years ago, but the new fossil rewrites the timeline to 635 million years ago.
Shuhai Xiao, a professor of geosciences at Virginia Tech College of Science, said, “ The question used to be, ‘Were there fungi in the Earth realm before the emergence of land plants? ‘
And I think our study suggests yes. Our fungal fossil is 240 million years older than the previous record. This is the oldest mention of land fungi so far. ‘