World Congress of Malacology Antwerp ... - Unitas Malacologica

demonstrated to be a different structure, then a new light could be shed on the evolution of the
foregut in Neogastropoda, especially as more anatomical data on other cancellariids will be available.
Millennial-timescale environmental changes recorded by molluscan fauna at Nussloch
(Germany) during the last glaciation and perspectives in quantitative palaeoclimatic
reconstructions in quaternary malacology
Moine, Olivier 1 ; Rousseau, Denis-Didier 1,2 ; Antoine, Pierre 3
1. Institut des Sciences de l’Evolution, Université Montpellier II, Place Eugène Bataillon, cc
61, 34095 Montpellier Cedex 05, France,
Email: omoine@isem.univ-montp2.fr; denis@dstu.univ-montp2.fr
2. Lamont-Doherty Earth Observatory of Columbia Observatory, Palisades, NY 10964, USA,
3. Laboratoire de Géographie Physique, 1 Place Aristide Briand, 92195 Meudon Cedex,
France,
Email: pierre.antoine@cnrs-bellevue.fr
The millennial-timescale climatic variability of the last glaciation has already been shown through
the study of ice- and marine-cores in the North Atlantic area. Its influence on European environments
was mainly studied in Mediterranean domain through long pollen records and speleothems, which
lack in continental domain. The terrestrial molluscs, sampled every 10 cm in the loess section of
Nussloch (Germany), thus provides a high-resolution record of millennial-scale environmental
changes between -70000 and -20000 years that has been correlated with the GRIP ice-core
(Greenland). Increases in mollusc abundance and juvenile proportions are linked with warmer phases,
i.e. Dansgaard-Oeschger interstadials.
These cyclical climatic oscillations also triggered humidity and vegetation changes recorded by
malacological populations and sedimentological features. The pattern proposed for the Upper
Pleniglacial (-35 to -20 kyr) is also valid for the Lower Pleniglacial (-75 to -50 kyr) with some
differences, but partly differs for the Middle Pleniglacial due to a lower sedimentation rate and
warmer climatic conditions. Moreover, according to the composition of the malacofauna, each
interstadial has a particular environmental signature in terms of temperature, humidity and
vegetation.
In Western Europe, Upper Weichselian malacofauna from England, northern France and Benelux are
similar, poor and homogeneous through the whole Upper Pleniglacial indicating a persistence of
homogeneous and poorly vegetated environments. In the Rhine Valley, the malacofauna are richer
and partly different from site to site. However, this relative richness varies synchronously with
sedimentological features through the Upper Weichselian. In four sites from this area, the
development of tundra soils is associated with cold and moister conditions reflected by poorer
malacofauna, which tend to resemble those observed in North- Western Europe. This suggests the
occurrence of cyclical shifts to the East of the environmental conditions prevailing in North-Western
Europe in response to millennial timescale changes of the climate dynamics.
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