Reconstruction of the Late Miocene climate of Spain using rodent palaeocommunity successions: an application of end-member modelling

摘要: Abstract End-member modelling is applied to a data set of relative abundances 67 Upper Miocene rodent associations (11–6 Ma) from Spain, France, Austria and Greece. The analysis results in the robust estimation levels four climatic parameters: humidity, temperature, seasonality type predictability. In preparatory stage, species are aggregated into nine groups on basis ecological criteria. Humidity preferences adaptations based actualistic functional morphological interpretations dentition locomotion. Temperature inferred palaeobiogeographic distributions. Levels adaptation (wet–dry or cool–warm seasonality) assigned diversities present-day climate/vegetation zones, ability extant relatives hibernate. Demographic used formulate (un)predictability. compositions unmixed contributions end members. These extreme, theoretical interpreted terms, their samples for parameters. subset 44 well-dated Calatayud-Daroca Teruel basins (NE Spain) construct detailed curves Late Miocene, while geographical dimension calculate inter-basinal differences. model Spain indicate more humid cooler conditions between 10.5 8.5 Ma, around 7, 6 arid warmer before 10.5, 8.6 7.5 Ma 6.5 Ma. Superimposed this pattern shift predictable, seasonal climate towards unpredictable, wet–dry 9.4 8.2 Inter-basinal comparisons per time slice show that southern Europe was dryer, warmer, unpredictable than central Europe, vegetational boundaries two regions were sharp. occurrences episodes during might be explained by southward migrations boundary temperate subtropical-dry belt associated vegetation types. Various positive correlations observed rodent-based other palaeoclimatic records Mediterranean NE Atlantic region (clay minerals, marine fauna, stable isotopes). cooling maxima at 7 closely correspond clusters events which generally considered reflect global ice volume.