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Here we present the first tephrostratigraphic, palaeomagnetic, and multiproxy data from a new ~98 m-deep sediment core retrieved from the Fucino Basin, central Italy, spanning the last ~430 kyr. Palaeoenvironmental proxy data (Ca-XRF, gamma ray and magnetic susceptibility) show a cyclical variability related to interglacialglacial cycles since the Marine Isotope Stage (MIS) 12-MIS 11 transition. More than 130 tephra layers are visible to the naked eye, 11 of which were analysed (glass-WDS) and successfully correlated to known eruptions and/or other equivalent tephra. In addition to tephra already recognised in the previously investigated cores spanning the last 190 kyr, we identified for the first time tephra from the eruptions of: Tufo Giallo di Sacrofano, Sabatini (288.0 ± 2.0 ka); Villa Senni, Colli Albani (367.5 ± 1.6 ka); Pozzolane Nere and its precursor, Colli Albani (405.0 ± 2.0 ka, and 407.1 ± 4.2 ka, respectively); and Castel Broco, Vulsini (419-490 ka). The latter occurs at the bottom of the core and has been 40 Ar/ 39 Ar dated at 424.3 ± 3.2 ka, thus providing a robust chronological constrain for both the eruption itself and the base of the investigated succession. Direct 40 Ar/ 39 Ar dating and tephra geochemical fingerprinting provide a preliminary radioisotopic-based chronological framework for the MIS 11-MIS 7 interval, which represent a foundation for the forthcoming multiproxy studies and for investigating the remaining ~110 tephra layers that are recorded within this interval. Such future developments will be contribute towards an improved MIS 11-MIS 7 Mediterranean tephrostratigraphy, which is still poorly explored and

Aim To understand the impact of glacial refugia and migration pathways on the modern genetic diversity of Pinus sylvestris . LocationThe study was carried out throughout Europe.Methods An extended set of data of pollen and macrofossil remains was used to locate the glacial refugia and reconstruct the migrating routes of P. sylvestris throughout Europe. A vegetation model was used to simulate the extent of the potential refugia during the last glacial period. At the same time a genetic survey was carried out on this species. ResultsThe simulated distribution of P. sylvestris during the last glacial period is coherent with the observed fossil data, which showed a patchy distribution of the refugia between c . 40 ° N and 50 ° N. Several migrational fronts were detected within the Iberian and the Italian peninsulas, and outside the Hungarian plain and around the Alps. The modern mitochondrial DNA depicted three different haplotypes for P. sylvestris . Two distinct haplotypes were restricted to northern Spain and Italy, and the third haplotype dominated most of the present-day remaining distribution range of P. sylvestris in Europe. Main conclusionsDuring the last glacial period P. sylvestris was constrained under severe climatic conditions to survive in scattered and restricted refugial areas. Combining palaeoenvironmental data, vegetation modelling and the genetic data, we have shown that the long-term isolation in the glacial refugia and the migrational process during the Holocene have played a major role in shaping the modern genetic diversity of P. sylvestris in Europe. Editor: Martin Sykes BIOSKETCHESRachid Cheddadi is a senior research scientist at CNRS. He is a palaeoecologist with particular focus on quantitative past climate reconstructions and vegetation dynamics from pollen records.

The scarcity of high-resolution empirical data directly tracking diversity over time limits our understanding of speciation and extinction dynamics and the drivers of rate changes. Here, we analyze a continuous species-level fossil record of endemic diatoms from ancient Lake Ohrid, along with environmental and climate indicator time series since lake formation 1.36 million years (Ma) ago. We show that speciation and extinction rates nearly simultaneously decreased in the environmentally dynamic phase after ecosystem formation and stabilized after deep-water conditions established in Lake Ohrid. As the lake deepens, we also see a switch in the macroevolutionary trade-off, resulting in a transition from a volatile assemblage of short-lived endemic species to a stable community of long-lived species. Our results emphasize the importance of the interplay between environmental/climate change, ecosystem stability, and environmental limits to diversity for diversification processes. The study also provides a new understanding of evolutionary dynamics in long-lived ecosystems.

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Lake-level records from Italy suggest a north–south climatic partition in the Central Mediterranean during the Holocene with respect to precipitation, but the scarcity of reliable palaeoclimatic records in the North and Central-Southern Mediterranean means new evidence is needed to validate this hypothesis. Here, we provide robust quantitative estimates of Holocene climate in the Mediterranean region based on four high-resolution pollen records from Northern (Lakes Ledro and Accesa) and Southern (Lakes Trifoglietti and Pergusa) Italy. Multiple methods are used to provide an improved assessment of the paleoclimatic reconstruction uncertainty. The multi-method approach uses the pollen-based Weighted Averaging, Weighted-Average-Partial-Least-Squares regression, Modern Analogues Technique, and the Non-Metric-Multidimensional Scaling/Generalized-Additive-Model methods. The precipitation seasonality reconstructions are validated by independent lake-level data, obtained from the same records. <br><br> A climatic partition between the north and the south during the Holocene confirms the hypothesis of opposing mid-Holocene summer precipitation regimes in the Mediterranean. During the early-to-mid-Holocene the northern sites (Ledro, Accesa) are characterized by minima for summer precipitation and lake-levels while the southern sites (Trifoglietti, Pergusa) are marked by maxima for precipitation and lake-levels. During the late Holocene, both pollen-inferred precipitation and lake-levels indicate the opposite pattern, a maximum in North Italy and a minimum in Southern Italy/Sicily. Summer temperatures also show partitioning, with warm conditions in Northern Italy and cool conditions in Sicily during the early/mid-Holocene, and a reversal during the Late-Holocene. <br><br> Comparison with marine cores from the Aegean Sea suggests that climate trends and gradients observed in Italy shows strong similarities with those recognized from the Aegean Sea, and more generally speaking in the Eastern Mediterranean

The sediment record from Lake Ohrid (Southwestern Balkans) represents the longest continuous lake archive in Europe, extending back to 1.36 Ma. We reconstruct the vegetation history based on pollen analysis of the DEEP core to reveal changes in vegetation cover and forest diversity during glacial–interglacial (G–IG) cycles and early basin development. The earliest lake phase saw a significantly different composition rich in relict tree taxa and few herbs. Subsequent establishment of a permanent steppic herb association around 1.2 Ma implies a threshold response to changes in moisture availability and temperature and gradual adjustment of the basin morphology. A change in the character of G–IG cycles during the Early–Middle Pleistocene Transition is reflected in the record by reorganization of the vegetation from obliquity- to eccentricity-paced cycles. Based on a quantitative analysis of tree taxa richness, the first large-scale decline in tree diversity occurred around 0.94 Ma. Subsequent variations in tree richness were largely driven by the amplitude and duration of G–IG cycles. Significant tree richness declines occurred in periods with abundant dry herb associations, pointing to aridity affecting tree population survival. Assessment of long-term legacy effects between global climate and regional vegetation change reveals a significant influence of cool interglacial conditions on subsequent glacial vegetation composition and diversity. This effect is contrary to observations at high latitudes, where glacial intensity is known to control subsequent interglacial vegetation, and the evidence demonstrates that the Lake Ohrid catchment functioned as a refugium for both thermophilous and temperate tree species.

Vegetation patterns during the 1st millennium AD in the central Mediterranean, exhibit a great variability, due to the richness of these habitats and the continuous shaping of the environment by human societies. Variations in land use, witnessed in the pollen record, reflect the role that local vegetation and environmental conditions played in the choices made by local societies. The interdisciplinary study of off-site cores remains the key evidence for palaeoenvironmental transformations mirroring the ‘semi-natural’ vegetation, and revealing temporal fluctuations and the amount of human impact on a regional scale.