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We thank J.A. López-Saéz for very useful comments that improved the quality of the manuscript. We also thank two anonymous reviewers for their useful suggestions. JVRD was supported by "Severo Ochoa" PhD Grant (BP 12-093) and by funding through "Ayuda para Estancias Breves" (EB15-12) for a research stay at Masaryk University (Brno, Czech Republic) in 2015. Both grants were provided by the "Plan de Ciencia, Tecnología e Innovación" (PCTI) Government of Principado de Asturias. BJA was supported by the project Employment of Best Young Scientists for International Cooperation Empowerment (CZ.1.07/2.3.00/30.0037) co-financed from the European Social Fund and the state budget of the Czech Republic. MC was supported by the Czech Science Foundation (Centre of Excellence PLADIAS, 14-36079G). ; Areas of Quaternary refugia for tree species have been mainly delineated based on fossil records and phylogeography, but niche modelling can provide useful complementary information. Here we use palaeodistribution modelling to test the main hypotheses about the distribution of Castanea sativa in the Last Glacial Maximum (LGM) and the mid-Holocene in Europe. We computed distribution models for current climatic conditions using different methods, and projected them onto three climatic scenarios for the LGM and the mid-Holocene. The projections were validated with pollen and charcoal records. LGM refugia were suggested in the north of the Iberian, Italian and Balkan Peninsulas, and in northern Anatolia. The projections for the mid-Holocene indicated high climatic suitability and geographic expansion of the species range across southern Europe, including some areas where the species is nowadays considered as non-native. In general, our models are consistent with the patterns proposed with pollen and charcoal records, and partially also with phylogeographic information inferred from genetic data, suggesting that the most suitable areas for C. sativa were extended significantly during the mid-Holocene, but declined afterwards and lost connectivity. The projected patterns were compatible with existing palaeobotanical records of C. sativa and provide a spatially-explicit picture of the species past distribution.

Universidad de Oviedo (project UNOV-13-EMERG-13) and European Commission, 7th Framework Program (Grant 613520, Project AGFORWARD). JVRD is in receipt of a Severo Ochoa PhD Grant (BP 12-093, FICYT-Government of Principado de Asturias) and a FP7-Marie Curie-COFUND grant ('Clarín' ACA17-02, Government of Principado de Asturias and European Commission)

In bears, reproduction is dependent on the body reserves accumulated during hyperphagia. The Cantabrian brown bear mainly feeds on nuts during the hyperphagia period. Understanding how landscape heterogeneity and vegetation productivity in human-dominated landscapes influence the feeding habits of bears may therefore be important for disentangling species-habitat relationships of conservation interest. We determined the spatial patterns of nut consumption by brown bears during the hyperphagia period in relation to landscape structure, characteristics of fruit-producing patches and vegetation productivity. For this purpose, we constructed foraging models based on nut consumption data (obtained by scat analysis), by combining vegetation productivity data, topographical variables and landscape metrics to identify nut foraging patterns during this critical period for bears. The average wooded area of patches where scats were collected and where the nuts that the bears had consumed were produced was larger than that of the corresponding patches where nuts were not produced. For scats collected outside of nut-producing patches, the distance between the scats and the patches was greatest for chestnut-producing patches. Elevation, Gross Primary Production (GPP) and the Aggregation Index (AI) were good predictors of acorn consumption in the models. Good model fits were not obtained for data on chestnut consumption in bears. The findings confirm that brown bears feeding on nuts show a preference for relatively large, highly aggregated patches with a high degree of diversity in the landscape pattern, which may help the bears to remain undetected. The nut prediction model highlights areas of particular importance for brown bears during hyperphagia. The human presence associated with sweet chestnut forest stands or orchards may make bears feel more vulnerable when feeding. ; J.C. Pérez-Girón is in receipt of a "Severo Ochoa" PhD Grant provided by the Government of Principado de Asturias (PA-18-PF-BP17-026). J.V. López-Bao ...