Revisiting Europe's temperate forests: Palaeoecological evidence for an herbivory-driven woodland-grassland mosaic biome

Understanding the pre-Homo sapiens baseline of the temperate forest biome is crucial for interpreting present-day biodiversity patterns, ecosystem functioning, and guiding restoration. In this review, we synthesize palaeoecological and ecological evidence to reassess vegetation structure across humid-temperate Europe during the Neogene (23–2.6 Myr) and Quaternary (2.6 Myr–1900 CE). We integrate data from multiple proxies – including pollen, macrofossils, isotopic composition, dental ecometrics, microcharcoal, and ancient environmental DNA – to evaluate whether Europe's temperate biome was dominated by closed-canopy forests, open grassland or by more heterogeneous woodland–grassland mosaics. Converging lines of evidence indicate that mosaic woodland vegetation – landscapes combining open, loosely wooded, and closed-canopy patches – prevailed throughout these periods, likely in large part maintained by abundant wild large herbivores. Following the Late-Pleistocene megafaunal collapse, tree cover expanded under reduced herbivore pressure. From the Mesolithic onward, humans increasingly shaped vegetation through burning and hunting. Since the Neolithic, our ancestors partially recreated lost disturbance dynamics through the use of domestic herbivores but also introduced novel drivers that produced ecosystems without historical analogues. These results challenge the traditional paradigm of closed-canopy forests being the dominant natural vegetation type in Europe, showing that homogenous closed-canopy forests are a recent phenomenon that only became the dominant “natural” vegetation after the decline of wild large herbivores and the loss of historical cultural management. Recognizing the woodland-grassland mosaic biome as the dominant natural baseline has major implications for conservation, rewilding, and biodiversity restoration strategies that reflect the ecological and evolutionary history of the temperate zone.