A long held belief about Europe natural past is being challenged by new research that suggests the continent was not once covered by dense, unbroken forests. Instead, scientists say Europe spent much of the last 23 million years as a diverse landscape of grasslands, meadows, shrubs and scattered trees.
The study, published in the journal Biological Conservation, brings together evidence from pollen records, plant fossils, ancient DNA, charcoal remains and chemical traces preserved in animal teeth. Researchers from Aarhus University in Denmark found that the image of a dark, closed-canopy forest stretching across Europe is largely a modern assumption rather than a historical reality.
For decades, ecologists have worked under the “closed-forest paradigm,” which held that dense forests were Europe’s natural state before human activities transformed the landscape. This idea has influenced conservation policies, reforestation projects and ecological restoration efforts across the continent.
However, the new review paints a very different picture. According to lead researcher Szymon Czyzewski, the evidence consistently points to open and dynamic environments rather than continuous woodland. Across millions of years, Europe’s landscapes were shaped by a mixture of grasslands, flower-rich meadows, scrubland and patches of woodland that shifted in response to climate and wildlife populations.
The researchers paid particular attention to the Eemian period, a warm interval between ice ages that lasted from about 130,000 to 115,000 years ago. During this time, roughly 60 percent of temperate Europe was covered by open woodland rather than dense forest. Pollen samples from locations stretching from Britain to Poland showed a greater presence of plants that thrive in sunlight, while charcoal evidence indicated that low intensity grassland fires were common.
Large herbivores played a crucial role in maintaining these open environments. Straight tusked elephants, rhinoceroses, wild horses, bison and aurochs regularly grazed and browsed vegetation preventing forests from becoming too dense. Their activities created a patchwork of habitats that supported a wide variety of plant and animal species.
Before modern humans became widespread, temperate Europe supported an estimated 25 to 50 tons of large-animal biomass per square mile. Today, that figure has fallen dramatically to around two tons per square mile. Researchers estimate that Europe has lost about 70 percent of its large animal species diversity and 95 percent of its herbivore biomass since the last interglacial period.
The study argues that the disappearance of many large herbivores between 40,000 and 15,000 years ago significantly altered Europe’s ecosystems. As grazing pressure declined, tree cover expanded and open habitats gradually disappeared. Scientists believe this shift was linked more closely to human hunting than to climate change, as previous ice ages had not caused similar extinctions.
Senior author Jens Christian Svenning says the findings have important implications for modern conservation strategies. He argues that current tree-planting programmes may not always restore Europe’s original ecological conditions. Many species that evolved in open habitats, including wildflowers, butterflies and ground-nesting birds, often struggle in dense plantations.
Instead, the researchers advocate “trophic rewilding,” a conservation approach that focuses on restoring populations of large grazing animals and allowing them to shape landscapes naturally. They suggest that grasslands, scrublands and open woodlands should no longer be viewed as degraded forests but as important and historically natural ecosystems.
The findings challenge one of Europe’s most influential environmental assumptions and could reshape future debates about reforestation, biodiversity conservation and ecosystem restoration. According to the researchers, Europe’s ancient wilderness was not a silent sea of trees but a vibrant mosaic of open habitats maintained by the continent’s once-abundant megafauna.