The history of variations in water level of Lake Constance, as reconstructed from sediment and pollen analysis of a sediment sequence from the archaeological site of Arbon-Bleiche 3, shows an abrupt rise in lake level dendrochronologically dated to 5375 yr ago (5320 yr relative to AD 1950). This event, paralleled by the destruction of the Neolithic village by fire, provoked the abandonment of this prehistoric lake-shore location established in the former shallow bay of Arbon-Bleiche, and was the last of a series of three episodes of successively higher lake level, the first occurring at 5600–5500 cal yr B.P. The dendrochronologically dated rise event was synchronous with an abrupt increase in atmospheric 14C. This supports the hypothesis of an abrupt climate change forced by varying solar activity. Moreover, the three successive episodes of higher lake level between 5600 and 5300 cal yr B.P. at Arbon-Bleiche 3 coincided with climatic cooling and/or changes in moisture conditions in various regions of both hemispheres. This period corresponds to the mid-Holocene climate transition (onset of the Neoglaciation) and suggests inter-hemispheric linkages for the climate variations recorded at Arbon-Bleiche 3. This mid-Holocene climate reversal may have resulted from complex interactions between changes in orbital forcing, ocean circulation and solar activity. Finally, despite different seasonal hydrological regimes, the similarities between lake-level records from Lake Constance and from Jurassian lakes over the mid-Holocene period point to time scale as a crucial factor in considering the possible impact of climate change on environments.

Over 300 goat/sheep faeces from the Neolithic lake-shore settlement of Arbon Bleiche 3 (3384–3370 bc) were analysed for macrofossils and 22 of them for pollen. Two main types of fodder could be detected, which were both consumed in winter. The more frequent type is characterized by remains of blackberry ( Rubus fruticosus s. l.) probably showing the use of pasture in the near surroundings of the settlement. The second type is dominated by leaf fragments of silver fir ( Abies alba) and by pollen and anthers of early-flowering shrubs such as hazel ( Corylus avellana) and alder ( Alnus sp.), pointing in the latter cases to additional foddering of twigs to livestock inside the settlement in times of shortage. Comparison with other Neolithic sites of Switzerland reveals differences that may indicate local adaptations in the keeping of goats or sheep.

During paleoparasitological analyses on several Neolithic sites in Switzerland (Arbon-Bleiche 3) and southwestern Germany (Hornstaad-Hörnle I, Torwiesen II, and Seekirch-Stockwiesen), numerous eggs of Diphyllobothrium sp. were recovered. This is one of the earliest occurrences of this parasite during the prehistoric period in the Old World. The prevalence of this helminth in the samples studied raises the question as to how important parasitic diseases were during the Neolithic period and what their actual consequences were.

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Dioctophymidae eggs were found in human coprolites dated from 3,384 to 3,370 BC from the site Arbon-Bleiche 3, Switzerland. This is the first record of dioctophymiasis in archaeological material. The important percentage of this disease in the studied coprolites raises the question of a higher prevalence during the Neolithic than at present.