Wild and domesticate mammals drove late-Holocene alpine plant diversity

In the face of land use and climate change, it is essential to know the key drivers of plant diversity in mountain regions. The relative roles of climate vs ungulates in alpine ecosystem change has been vigorously debated. Neither observational data nor traditional palaeoecological data can resolve this issue over decadal to centennial timescales, but sedimentary ancient DNA can. Here we record 603 plants, 5 wild and 6 domestic mammals over the last 14 000 years in European Alps. Sheep were the first domestic animals detected (5.8 ka), with cattle appearing at the onset of the Bronze Age (4.2 ka), and goats arriving later (3.5 ka). While sheep had an impact similar to wild ungulates, cattle became the primary driver of plant diversity over the last 2 ka. Modelling of the DNA data reveals a significantly larger effect of cattle and wild ungulates than temperature on plant diversity. Our findings highlight the significant alteration of alpine vegetation and the entire ecosystem in the Alps by wild and domestic herbivores. While sheep grazing mirrors the influence of wild herbivores, the introduction of cattle led to the most notable increase in plant diversity of the last 14.000 years. This study has immediate implications for the mitigation of climate change in mountain regions.