Forest growth may be responsible for the extinction of European megafauna. This has been reported by the Johannes Gutenberg University of Mainz.
Megafauna such as mammoths, bison and woolly rhinos lived for tens of thousands of years in the prehistoric plains of present-day Central Europe. They completely disappeared from the region about 11,000 years ago, and the reason is not fully understood by scientists.
To do this, the scientists analyzed sediment from layers of sediment taken from two maars — volcanic craters that later turned into lakes — in the Eifel Highlands. The researchers used these to reconstruct changes in megafauna abundance and landscape in the region over the past 60,000 years. First of all, they were interested in pollen and fungal spores deposited in the stone. While pollen is evidence of past vegetation, fungal spores are evidence of the existence of large mammals because some molds only colonize the feces of large herbivores.
The results showed that human hunters and large mammals did indeed coexist here for several thousand years. “The deposits from the Eifel maars have not provided us with any evidence that humans were responsible for the extinction of these animals,” the scientists explain. Therefore, the overfishing hypothesis that explains the extinction of the North American megafauna is not supported for Central Europe.”
Based on the study of pollen grains, the researchers found that 60,000 – 48,000 years ago the Eifel was covered with spruce forests, which during the cooling turned into a more open forest-steppe. This type of land remained dominant until 43,000 to 30,000 years ago. Later, the forest-tundra of the Eifel turned into the polar desert of the Ice Age, where only grass grew.
Spores of the fecal fungi of the megafauna suggest that large mammals lived in this particular environment 48,000 to 11,000 years ago. Bones found in caves in Belgium and gravel beds in the Rhine Valley show that mammoths, woolly rhinos, bison, horses and reindeer prefer cold climates. The sparse forests of warmer periods were the preferred habitat for deer and bison.
“As trees began to take control, large herbivores lost access to their staple food, namely grass,” the authors explain. “Neither extreme climate fluctuations in the last 60,000 years, nor local volcanic activity and associated fires seem to have played a role in their extinction.”