UvA palaeoecologist Bas van Geel and his team have gained new insights regarding the landscape, the range of foods and the food choices of large grazing animals during the last Ice Age and the start of the warm period following the Ice Age. They have managed to do this by identifying the pollen from the folds in the molars of large grazers.
Since there are many amateur fossil hunters in the Netherlands, we already have a good picture of which animals lived on the mammoth steppes. But very little is known about what the animals ate back then.
The palaeobiologists studied 52 molars from eight different species of grazers: red deer, reindeer, moose, musk ox and four extinct species: steppe bison, woolly rhinoceros, giant deer and Merck’s rhinoceros. The Dutch Association for the study of Pleistocene Mammals collected the molars; this collaboration between the collectors and researchers was of great importance to the research.
The pollen from folds in the molars showed what the animals ate and this in turn gave a picture of the living environment of the animals.
Previous research by Van Geel had already shown that the giant deer ate mostly wormwood. This finding has now been backed up by the examination of another 10 fossil giant deer molars. Current research shows that woolly rhinoceros, reindeer and steppe bison also ate a lot of wormwood, which would indicate that this plant was very widespread.
When examining the molars of Merck’s rhinoceros, the researchers mostly found pollen from alder and hazel, mistletoe, ferns and ivy. This indicates that the animal lived in wooded environments, before the most recent Ice Age began.
The molars of the red deer revealed traces of alder and water plants – the food that red deer still eat today.
The fossil molars also contained pollen from plants pollinated by insects. However, these plants produce very small amounts of pollen, so it is very hard to identify in samples from peat and seafloors. ‘Thanks to this discovery, we now know, for instance, that Helianthemum (rock rose, sunrose) grew on the mammoth steppe. As well as the Impatiens genus of flowering plants. That’s a type that I hadn’t expected there’, says Van Geel.
Ultimately, each grazing animal has its own preferences, so the results might give a distorted picture. Moreover, it’s possible that not every eaten plant species leaves the same amount of pollen in the jaws, so Van Geel isn’t finished with his research yet: ‘I’d like to look at this issue with the species still alive today, which would be good follow-up research.’
Bas van Geel a researcher at the Institute of Biodiversity and Ecosystem Dynamics (IBED).