How A 407-Million-Year-Old Fossil From Scotland Revealed One Of Earth’s Oldest Plant-Fungus Partnerships

If you walk through a forest today, you will find that the trees are silently connected to a network of fungi deep within the forest. This allows the plants to draw nutrients from the forest floor. What’s fascinating is that this process has been going on for hundreds of millions of years.

A fossil discovered in Scotland has now offered a rare look at how early this connection began. Scientists studying a plant fossil from the Rhynie Chert formation found evidence of a previously unknown fungus living inside plant cells about 407 million years ago.

The fungus has been named Rugososporomyces lavoisierae. Researchers say the discovery provides one of the clearest views yet of how plants and fungi worked together during the early days of life on land.


The findings were described by scientists from the Natural History Museum and the University of Cambridge in research shared through the Natural History Museum press office. The work also appears in reports that summarize important fossil discoveries highlighted by the Elevation Science field journal.



A New Fossil Species Hidden Inside An Ancient Plant

The fossil comes from the Early Devonian period, a time when plants were only beginning to establish themselves on land. Life on the continents was still new and difficult. Soil nutrients were limited, and the environment was very different from modern ecosystems.

Inside the fossilized plant tissues, researchers identified structures belonging to a fungus that had never been described before. The species was later named Rugososporomyces lavoisierae.

Unlike many fossils that show only surface impressions, this specimen preserved tiny cellular details. That allowed scientists to study how the fungus interacted with the plant itself.

Researchers explained in the Natural History Museum research announcement titled “Advanced Imaging Reveals New Fungus Species in 407-Million-Year-Old Plant Fossil” that the fungus had grown directly inside plant cells. The structures formed by the fungus looked like tiny branches spreading through the cell.

These structures are known as arbuscules. They are one of the key signs of a biological partnership called mycorrhiza.

Mycorrhiza describes a relationship where fungi and plants exchange nutrients. The fungus collects minerals such as phosphorus from the soil, while the plant provides sugars created through photosynthesis. In the scientific overview “Mycorrhiza,” and in ecological research published in the journal Trends in Plant Science, it is explained that this exchange allows both organisms to survive in challenging environments.

Finding these structures in such an old fossil confirms that plants and fungi were cooperating very early in Earth’s history.

How Modern Imaging Revealed A 400-Million-Year-Old Relationship

One thing that makes this discovery special is the technology that was used. It is not as though scientists looked at the fossil in an old-fashioned way. Rather, they took advantage of the latest technology, including confocal microscopy and fluorescence lifetime imaging microscopy, to look inside the fossil.

The Natural History Museum research team explained that these methods helped them clearly separate fungal structures from plant tissue. This produced detailed images showing the fungus entering plant cells and spreading through them.

In the past, most fossils could only be studied in thin slices under a microscope. Modern imaging allows scientists to explore ancient life with far greater clarity.

This approach is transforming paleontology. Researchers can now study how organisms interacted with each other millions of years ago rather than just identifying isolated fossils.

Significantly, the Rhynie Chert site has a major role to play in these findings. Geological investigations described in the scientific literature pertaining to the ecosystems of the Early Devonian period state that this deposit contains entire communities of early land organisms. Plants, fungi, bacteria, and small animals were rapidly mineralized in silica-rich waters.

Because of that unusual preservation, the site acts almost like a natural time capsule from the dawn of terrestrial life.

The discovery of Rugososporomyces lavoisierae adds another piece to the story of how plants first adapted to land. Early plants struggled with poor soil and limited nutrients. Fungal partners helped solve that problem.

Scientists studying ancient ecosystems now believe that mycorrhizal partnerships were one of the key innovations that allowed plants to spread across continents. Over time, these partnerships helped shape forests, soils, and food webs.

Today, an analogous network exists beneath most plants on Earth. The quiet cooperation that helped ancient plants survive 400 million years ago continues to support life in our world. The survival strategy that began in a harsh ancient world has grown into the green world we see today.