Showcase 14
In the laboratory – Down to the last detail
Wood, plant remains, animal bones, fish scales, seeds and even tiny things such as pollen are well preserved under water without oxygen. Their analysis provides answers to questions about the environment its occupation by humans.
Piles and other wooden remains enable dating using dendrochronology. To do this, the distances between a tree’s annual rings are measured. Comparing the ring patterns makes it possible to determine the felling date of the trees and thus the construction date of a pile dwelling.
In drill cores, different layers of soil can be easily differentiated. A detailed examination shows the core’s components: lake deposits, charcoal, clay, seeds, fruits and plant residues. Even the smallest pollen grains are visible under the microscope. This makes it possible to draw conclusions about the environment of the pile-dwelling settlements: the plants on the bank edge, the pastures and arable land as well as cultivated and wild plants can be identified. Pollen shows the composition of the forest and its changes over thousands of years.
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Layered deposits Sipplingen-Osthafen
In this underwater image, light and dark layers can be recognised next to the piles.
The dark layers indicate the presence of humans. They are known as cultural layers and can be recognised by wood, charcoal and blue hut clay deposits. The white layers are lake chalk, calcareous precipitates of algae that settle on the lake bed in undisturbed conditions. Numerous plant remains down to the smallest pollen grains are preserved in all layers. The age of the wood can be determined.
Photo: A. Müller/LAD
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The wooden piles of the former pile dwellings are still preserved in many places at Lake Constance. Black oak wood, which is shaped to a pointy cone by waves and sand, is typical. If they protrude from the ground sediment, they become increasingly weathered over the years until they disappear completely.
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Sawn-out slices of the original pile clearly show the annual rings of tree from which it was made.
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The distance between the annual rings shows very well the growth behavior and the weather conditions during the tree’s lifetime.
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Stake of a house | Oak | Itznang-Unter Eichen 3237 BC | LAD
The age of the tree and its felling date can be determined using dendrochronology (determining the age of tree rings).
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Profile sample | Cultural layer and lake chalk | 2800 BC | Schreckensee | LAD
The layers of earth from the lake bed show the places where people settled. By analysing the soil samples, clues can be found about the climate at that time, the water levels in the Stone Age and the shape of the landscape.
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Oak pollen
Photo: paldat
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Lime pollen
Photo: paldat/H. Halbritter
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Pea pollen
Photo: paldat/H. Halbritter
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White goosefoot pollen
Foto: paldat/B. Diethart
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Wild carrot pollen
Photo: paldat/H. Halbritter
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Flax pollen
Photo: paldat/H. Halbritter