A growing body of paleobotanical research is reshaping scientists’ understanding of how trees first colonised the planet, with newly analysed fossil sites in the United Kingdom and North America revealing forest ecosystems far older and more complex than previously thought. The latest findings, drawn from cliffs along the southwest coast of England and reinforced by studies in upstate New York, push the timeline of Earth’s earliest forests back by millions of years and offer fresh insight into how plants transformed the atmosphere, soils, and climate of the Devonian world more than 380 million years ago.
The Discovery That Changed the Devonian Timeline
Researchers from the University of Cambridge and Cardiff University identified what is now considered the world’s oldest known fossilised forest in sandstone cliffs near Minehead, on the Somerset and Devon coast. The fossils, dating to approximately 390 million years ago, predate the previous record-holder — the Gilboa fossil forest in New York State — by around four million years. The trees, known as Calamophyton, were palm-like in appearance but only two to four metres tall, with hollow trunks and branches that shed twig-like structures rather than leaves. The findings were published in the Journal of the Geological Society and have prompted a re-evaluation of how quickly land plants evolved into forest-forming organisms.
Lead author Professor Neil Davies described the discovery as a window into “a time when life on land was just starting to take off.” The site, originally surveyed decades ago, was revisited with modern imaging and sedimentological techniques, allowing researchers to map both the trees themselves and the surrounding river-channel deposits in unprecedented detail.
Why These Fossil Forests Matter
The significance of these discoveries reaches far beyond paleobotany. The arrival of forests during the Middle Devonian is widely credited with one of the most consequential transformations in Earth’s history: the drawdown of atmospheric carbon dioxide, the stabilisation of riverbanks, and the creation of the first true soils. As trees grew taller and rooted more deeply, they accelerated chemical weathering of silicate rocks — a process that pulled carbon out of the atmosphere and is thought to have triggered significant global cooling.
The Somerset fossil bed shows that even early, modestly sized trees were already shaping their environments. Sediment patterns preserved at the site indicate that the Calamophyton stands trapped debris and influenced the meandering of ancient river systems, foreshadowing the role modern forests play in landscape engineering. According to coverage by BBC News, the site represents the earliest evidence of trees actively modifying the physical world around them.
Connections to Gilboa and Ongoing Research
The Somerset findings complement decades of work at Gilboa, New York, where paleobotanists have reconstructed a slightly younger but more structurally diverse Devonian forest dominated by the cladoxylopsid Eospermatopteris and the lycopod-like Archaeopteris. Together, the two sites suggest that the transition from low-growing vegetation to forest canopies occurred in pulses across multiple continents, rather than as a single, isolated event.
Researchers note that Archaeopteris, in particular, marks a turning point: it possessed wood, branching like a modern tree, and deep roots, foreshadowing the architecture of conifers and flowering plants that would dominate later geological eras. The Somerset trees, by contrast, represent an earlier, more experimental phase of plant evolution — one in which the basic blueprint of “tree” was still being worked out.
What Comes Next
Paleobotanists are now turning their attention to other Devonian-aged sediments in Wales, Scotland, and the Canadian Maritimes in hopes of finding additional early-forest sites. Improved drone-based mapping and high-resolution sediment scanning are expected to make older, weathered exposures newly readable. As researchers continue to fill in the gaps between the earliest land plants and the towering Carboniferous swamps that followed, the Devonian is emerging as one of the most dynamic chapters in Earth’s biological history — a period when plants, quite literally, reshaped the planet.
For more stories on plant science, evolution, and the natural world, visit science.wide-ranging.com for related coverage and in-depth features.
