Aurochs, the massive and wild ancestors of modern cattle, were once among the most majestic creatures across Europe, Asia, and North Africa. However, their presence in Scandinavia came to an end much earlier than in the rest of Europe. A new study led by Lund University has combined ancient DNA analysis with archaeological findings to shed light on the tragic end of these giant mammals in the north [1].
Genetic Bottleneck and Isolation
According to the research, aurochs migrated northward from Western Europe approximately 11,700 years ago following the last Ice Age. However, this journey came at a genetic cost. DNA data indicates that a severe population bottleneck occurred as the animals spread into Scandinavia via Jutland. This reduction in genetic diversity weakened the herds' resilience against environmental stressors. While scientists previously believed this population became isolated 10,000 years ago, new data proves that contact with mainland Europe persisted until 8,000 years ago, when the flooding of the Danish-Swedish straits destroyed the land bridge [1].
Human Pressure and a Changing Landscape
Simultaneous with this isolation, increasing human settlements and intensive hunting rapidly drove down aurochs numbers. A similar process was observed in the extinction of the great auk, known as the Northern Hemisphere's version of the penguin, which vanished due to heavy human hunting pressure [2]. In Scandinavia, the decline that began with hunting reached an irreversible point with the spread of agriculture and the densification of forests. As open grasslands gave way to thick woodlands, it became nearly impossible for these giant herbivores to find sufficient forage [3].
A Combination of Multiple Factors
Researchers emphasize that it would be a mistake to attribute the extinction of the aurochs to a single cause. Already weakened by low genetic diversity, the herds could not simultaneously withstand both human hunting pressure and shifting climatic conditions. Small groups that held out in their final refuges in southern Sweden until 6,500 years ago eventually vanished as their habitat became completely fragmented. These findings once again highlight the transformative impact of human activities on ecosystems over thousands of years.
Sources and further reading
- [1] Study sheds new light on why aurochs disappeared in Scandinavia | Lund University
- [2] Ancient DNA confirms humans wiped out northern hemisphere’s version of the penguin
- [3] Habitat, Hunting, & Extinction of the Aurochs
Image & News Source: Archaeologymag / archaeologymag.com