Dense, dark forests have long been considered the original landscape of Europe. To date, many nature conservation projects aim to restore this seemingly natural state. But new research shows that dense forests are a modern phenomenon. Analyzes of pollen, fossils and sediments show that for millions of years our continent was characterized by a diverse mosaic of grasslands, bushes and trees, maintained by large herbivores. Most species native to this country are adapted to this open landscape. In order to preserve biodiversity and promote ecosystems typical of Europe, new strategies are required.
What did the “natural” landscape of Europe look like before humans shaped the continent? To this day, the image of dense primeval forests, whose closed treetops barely allow light to reach the ground, persists. Reforestation projects are therefore trying to create more intact forest areas based on this model, assuming that this is doing nature and biodiversity a service. But studies are increasingly showing that this supposed ideal is more like modern forests and has little in common with the original nature of Europe.
Evidence of the vegetation of the past
A team led by Szymon Czyżewski from Aarhus University in Denmark has now compiled extensive evidence that paints a very different picture of the European landscape over the last 23 million years: “Consistent evidence suggests that mosaic-like vegetation predominated – landscapes that combine open grassland, loosely wooded and closed forest patches and that were probably maintained largely by abundant wild large herbivores,” the researchers report.
For their study, Czyżewski and his colleagues combined numerous paleoecological evidence, including fossil pollen, plant macrofossils, charcoal particles from ancient fires, isotope analyzes from teeth and bones of herbivores, fossil insects and mammals, and environmental DNA preserved in sediments. “Each type of proxy offers its own perspective, but together they let us see whether the landscapes were covered by dense forests, open grasslands, or a mix of both,” explains Czyżewski. “By combining these datasets over a long period of time – from the Miocene to pre-industrial times – we were able to track long-term changes in vegetation and the role of large herbivores with much greater confidence than previous studies that used only one method.”
New paths for modern nature conservation
In Europe before the time of humans, mammoths, aurochs and the like trampled wide paths between the trees and thus created open areas in which a variety of wildflowers thrived. As humans gradually eradicated large wild herbivores, domesticated grazers initially assumed their ecological role. But as agriculture became increasingly industrialized, cows, sheep, pigs and goats were increasingly kept in stables and closely fenced pastures. Only this resulted in today’s strict separation between open meadows and fields and dense, dark forests.
“The ecosystems we see in Europe today are missing the large wild herbivores that not only shaped the landscapes but also maintained their biodiversity for millions of years,” says Czyżewski. “The most dramatic change has occurred largely over the last hundred years, as traditional extensive grazing disappeared from large parts of the landscape.”
To date, most animals and plants native to Europe are more adapted to open landscapes than to forests. Modern nature conservation practice, which primarily promotes forests as natural biotopes, runs counter to this. “This is not only harmful to biodiversity, but is also in direct contradiction to the ecosystems in which European species have developed over millions of years,” says Czyżewski’s colleague Jens-Christian Svenning. “Instead, restoration efforts should place greater emphasis on creating and maintaining mosaics of forest and open habitats – not least through the reintroduction of naturally occurring large herbivores.”
Source: Szymon Czyżewski (Aarhus University, Denmark) et al., Biological Conservation, doi: 10.1016/j.biocon.2026.111749