An international team of researchers, including emeritus professor Wil Roebroeks of Leiden University's Faculty of Archaeology, has uncovered evidence that modern fallow deer have lost much of the genetic diversity once present in their Ice Age ancestors. The findings have been published in iScience.
Genetic diversity
The study analysed ancient DNA from ten fallow deer specimens dating to around 125,000 years ago from the Neumark-Nord lake landscape in Germany, a site famous for its rich evidence of Neanderthal activity. Remarkably, the researchers found that this single ancient population possessed a level of genetic diversity comparable to that of all modern fallow deer across their current range, from Spain to Turkey.
The results suggest that multiple genetically distinct fallow deer lineages once inhabited Europe. However, climatic changes during the Ice Age appear to have eliminated many of these populations, leaving only a single lineage to survive in southern refuges. Humans later spread descendants of this surviving population across Europe and beyond.
Increasingly detailed picture
The findings also challenge a long-standing interpretation of the Neumark-Nord fallow deer. Based on their distinctive antlers and anatomy, they had previously been classified as a separate species or subspecies. The new genetic evidence indicates that they belonged to the same species as modern fallow deer.
For Roebroeks, the study is part of a broader research programme at Neumark-Nord. 'This study is the latest in a series of papers produced by the MONREPOS/Leiden University team following our joint excavations at Neumark-Nord,' he says. 'Together, these studies are providing an increasingly detailed picture of Neanderthal life, hunting practices and the rich ecosystems in which they lived.'
Shaping genetic history
The research highlights how climate change and human activity have shaped the genetic history of animal populations over tens of thousands of years and offers new insights relevant to biodiversity and conservation research today.
Publication
Alberto Rocha-Méndez, Patrick Arnold, Lutz Kindler, Sabine Gaudzinski-Windheuser, Wil Roebroeks, Fulco Scherjon and Michael Hofreiter, Eemian palaeogenetics demonstrates loss of diversity in modern fallow deer (Dama dama), iScience 29 (2026).
